Shoe sole orthotic structures and computer controlled compartments

ABSTRACT

This invention relates generally to footwear such as a shoe, including an athletic shoe, with a shoe sole, including at least one orthotic section formed at least in part by midsole material. The insertable midsole orthotic is removably inserted within the shoe upper, the sides of which hold it in position. The shoe sole includes a concavely rounded side or underneath portion, which may be formed in part by the insertable midsole orthotic. The insertable midsole orthotic may extend the length of the shoe sole or may form only a part of the shoe sole and can incorporate cushioning or structural compartments or components. The insertable midsole orthotic provides the capability to permit replacement of midsole material which has degraded or has worn out in order to maintain optimal characteristics of the shoe sole. Also, the insertable midsole orthotic allows customization for the individual wearer to provide tailored cushioning or support characteristics for the purpose of orthopedic, podiatric, corrective, prescriptive, therapeutic and/or prosthetic purposes. The shoe sole can also include at least one compartment containing a fluid, a flow regulator, a pressure sensor to monitor the compartment pressure, and a control system such as a computer processor, capable of automatically adjusting the pressure in the compartment(s) in response to the impact of the shoe sole with the ground surface.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to footwear such as a shoe, includingan athletic shoe, with a shoe sole, including at least one orthoticinsert formed at least in part by a midsole section (hereinafterreferred to as an “insertable midsole orthotic”). The insertable midsoleorthotic is preferably removable and is inserted within the shoe upper,the sides of which hold it in position, as may the bottom sole or otherportion of the midsole. The shoe sole includes a concavely rounded sideor underneath portion, which may be formed in part by the insertablemidsole orthotic. The insertable midsole orthotic may extend the lengthof the shoe sole or may form only a part of the shoe sole and canincorporate cushioning or structural compartments or components. Theinsertable midsole orthotic provides the capability to permitreplacement of midsole material which has degraded or has worn out inorder to maintain optimal characteristics of the shoe sole. Also, theinsertable midsole orthotic allows customization for the individualwearer to provide tailored cushioning or support characteristics fororthopedic, podiatric, corrective, prescriptive, therapeutic and/orprosthetic purposes. Finally, the insertable midsole orthotic can beemployed or modified to provide an orthotic inner shoe.

The invention further relates to a shoe sole which includes at least oneinsertable midsole orthotic, at least one chamber or compartmentcontaining a fluid, a flow regulator, a pressure sensor to monitor thecompartment pressure, and a control system capable of automaticallyadjusting the pressure in the chamber or compartment(s) in response tothe impact of the shoe sole with the ground surface, includingembodiments which accomplish this function through the use of a computersuch as a microprocessor.

2. Brief Description of the Prior Art

Many existing athletic shoes are unnecessarily unsafe. Many existingshoe designs seriously impair or disrupt natural human biomechanics. Theresulting unnatural foot and ankle motion caused by such shoe designsleads to abnormally high levels of athletic injuries.

Proof of the unnatural effect of many existing shoe designs has comequite unexpectedly from the discovery that, at the extreme end of itsnormal range of motion, the unshod bare foot is naturally stable andalmost impossible to sprain, while a foot shod with a conventional shoe,athletic or otherwise, is artificially unstable and abnormally prone toankle sprains. Consequently, most ordinary ankle sprains must be viewedas largely an unnatural phenomena, even though such ankle sprains arefairly common. Compelling evidence demonstrates that the stability ofbare feet is entirely different from, and far superior to, the stabilityof shod feet.

The underlying cause of the nearly universal instability of shoes is acritical but correctable design problem. That hidden problem, so deeplyingrained in existing shoe designs, is so extraordinarily fundamentalthat it has remained unnoticed until now. The problem is revealed by anovel biomechanical test, one that may be unprecedented in its extremesimplicity. The test simulates a lateral ankle sprain while standingstationary. It is easily duplicated and may be independently verified byanyone in a minute or two without any special equipment or expertise.The simplicity of the test belies its surprisingly convincing results.It demonstrates an obvious difference in stability between a bare footand a foot shod with an athletic shoe, a difference so unexpectedlynoticeable that the test proves beyond doubt that many existing shoesare unstable and thus unsafe.

The broader implications of this discovery are potentially far-reaching.The same fundamental problem in existing shoes that is glaringly exposedby the new test also appears to be the major cause of chronic overuseinjuries, which are unusually common in running, as well as otherchronic sport injuries. Existing shoe designs cause the chronic injuriesin the same way they cause ankle sprains; that is, by seriouslydisrupting natural foot and ankle biomechanics.

The applicant has introduced into the art the concept of a TheoreticallyIdeal Stability Plane as a structural basis for shoe sole designs. Thatconcept, as implemented into shoes such as street shoes and athleticshoes, is presented in U.S. Pat. Nos. 4,989,349, issued on Feb. 5, 1991;5,317,819, issued Jun. 7, 1994; and 5,544,429, issued on Aug. 13, 1996,as well as in PCT Application No. PCT/US89/03076 filed on Jul. 14, 1989and published as WO 90/00358, and many subsequent U.S. and PCT publishedapplications.

The purpose of the Theoretically Ideal Stability Plane as described inthese applications is primarily to provide a neutral shoe design thatallows for natural foot and ankle biomechanics without the seriousinterference from the shoe design that is inherent in many existingshoes.

In a second aspect, the shoe sole designs in this application are basedon a recognition that lifetime use of existing shoes, the unnaturaldesign of which is innately and seriously problematic, has producedactual structural changes in the human foot and ankle. Existing shoesthereby have altered natural human biomechanics in many, if not most,individuals to an extent that must be compensated for in an enhanced andtherapeutic design. The continual repetition of serious interferencewith natural biomechanics by existing shoes appears to have producedindividual biomechanical changes that may be permanent, so simplyremoving the cause is not enough. Treating the residual effect must alsobe undertaken.

Some attempts have been made to provide footwear which is anatomicallycorrect so as to increase the comfort of the wearer while at the sametime minimizing fatigue and injuries caused by the design of manyexisting shoes. For example, orthotic devices are well known in the artand are exemplified by U.S. Pat. No. 4,803,707 issued to Brown and U.S.Pat. No. 4,868,945 issued to DeBettignies. Some of these designs arebased on an analysis of the typical human gait. For example, U.S. Pat.No. 4,510,700 to Brown (“Brown '700”) provides a detailed discussion ofthe various phases of the human gait. In Brown '700, a plurality ofdifferent types of orthotic devices are provided from which anappropriate device can be selected based on the particular foot disorderto be treated. Brown '700 accomplishes this with the provision ofvariably adjustable shoe inserts.

A number of other patents disclose orthotic devices which may besuitably positioned within the shoe. These devices include complexcontours on their upper surfaces which are specially designed to addressthe peculiarities of a given foot. Examples of such devices aredisclosed in U.S. Pat. Nos. 2,669,814; 2,680,919; and 3,922,801.

Accordingly, it is a general object of one or more embodiments of thisinvention to elaborate upon the application of the principle of thenatural basis for the support, stability, and cushioning of the barefootto shoe designs.

It is still another object of one or more embodiments of the inventionto provide a shoe having a sole with natural stability which puts theside of the shoe upper under tension in reaction to destabilizingsideways forces on a tilting shoe.

It is still another object of one or more embodiments of this inventionto balance the tension force on the side of the shoe upper substantiallyin equilibrium to neutralize the destabilizing sideways motion by virtueof the tension in the sides of the shoe upper.

It is another object of one or more embodiments of the invention tocreate a shoe sole with support and cushioning which is provided by shoesole compartments, filled with a pressure-transmitting medium likeliquid, gas, or gel, that are similar in structure to the fat pads ofthe foot, which simultaneously provide both firm support and progressivecushioning.

A further object of one or more embodiments of the invention is toelaborate upon the application of the principle of the TheoreticallyIdeal Stability Plane to other shoe structures.

A still further object of one or more embodiments of the invention is toprovide a shoe having a sole rounded which deviates in a constructiveway from the Theoretically Ideal Stability Plane.

A still further object of one or more embodiments of this invention toprovide a sole rounded having a shape naturally rounded to the shape ofa human foot, but having a shoe sole thickness which is increasedsomewhat beyond the thickness specified by the Theoretically IdealStability Plane, either through most of the rounded of the sole, or atpre-selected portions of the sole.

It is yet another object of one or more embodiments of the invention toprovide a naturally rounded shoe sole having a thickness whichapproximates a Theoretically Ideal Stability Plane, but which variestoward either a greater or lesser thickness throughout the sole or atpre-selected portions thereof.

It is another object of one or more embodiments of the present inventionto implement one or more of the foregoing objects by employing aremovable midsole orthotic.

It is yet another object of one or more embodiments of the presentinvention to combine one or more of the foregoing objects with theability to customize the shoe design for a particular wearer's foot.

It is a still further object of one or more embodiments of the presentinvention to combine one or more of the foregoing objects with theability to replace one or more portions of the shoe in order tosubstitute new portions for worn portions or for the purpose ofcustomizing the shoe design for a particular activity.

It is a still further object of one or more embodiments of the presentinvention to provide the ability to automatically adjust variousproperties of the shoe or shoe sole using a computer controlledcompartment system.

It is a still further object of one or more embodiments of the presentinvention to provide an orthotic inner shoe formed from a combination ofone or more elements of the insertable midsole orthotic and/or computercontrolled compartment system.

These and other objects of the invention will become apparent from thesummary and detailed description of the invention which follow, takenwith the accompanying drawings.

SUMMARY OF THE INVENTION

In one aspect, the present invention attempts, as closely as possible,to replicate the naturally effective structures of the bare foot thatprovide stability, support, and cushioning. More specifically, theinvention relates to the structure of removable orthotic inserts formedat least in part by a midsole section and integrated into shoes such asathletic shoes. Even more specifically, this invention relates to theprovision of a shoe having an anthropomorphic sole including a removablemidsole orthotic that substantially copies the underlying support,stability and cushioning structures of the human foot. Natural stabilityis provided by balancing the tension force on the side of the upper insubstantial equilibrium so that destabilizing sideways motion isneutralized by the tension.

Still more particularly, this invention relates to support andcushioning which is provided by shoe sole compartments filled with apressure-transmitting medium like liquid, gas, or gel. Unlike similarexisting systems, direct physical contact occurs between the uppersurface and the lower surface of the compartments, providing firm,stable support. Cushioning is provided by the pressure-transmittingmedium progressively causing tension in the flexible and semi-elasticsides of the shoe sole. The compartments providing support andcushioning are similar in structure to the fat pads of the foot, whichsimultaneously provide both firm support and progressive cushioning.

Directed to achieving the aforementioned objects and to overcomingproblems with prior art shoes, a shoe according to one or moreembodiments of the invention comprises a sole having at least a portionthereof which is naturally rounded whereby the upper surface of the soledoes not provide an unsupported portion that creates a destabilizingtorque and the bottom surface does not provide an unnatural pivotingedge.

In another aspect, the shoe includes a naturally rounded sole structureexhibiting natural deformation which closely parallels the naturaldeformation of a foot under the same load. The shoe sole is naturallyrounded, paralleling the shape of the foot in order to parallel itsnatural deformation, and made from a material which, when under load andtilting to the side, deforms in a manner which closely parallels that ofthe foot of its wearer, while retaining nearly the same amount ofcontact of the shoe sole with the ground as in its upright state underload.

In another aspect, this invention relates to variations in the structureof such shoes having a sole contour which follows a Theoretically IdealStability Plane as a basic concept, but which deviates therefrom toprovide localized variations in natural stability. This aspect of theinvention may be employed to provide variations in natural stability foran individual whose natural foot and ankle biomechanical functioninghave been degraded by a lifetime use of problematic existing shoes.

This new invention is a modification of the inventions disclosed andclaimed in the applicant's previously mentioned prior patentapplications and develops the application of the concepts disclosedtherein to other shoe structures. In this respect, one or more of thefeatures and/or concepts disclosed in the applicant's prior applicationsmay be implemented in the present invention by the provision of aremovable midsole orthotic. Alternatively, one or more of the featuresand/or concepts of the present invention may be combined with theprovision of a removable midsole orthotic which itself may or may notimplement one of the concepts disclosed in the applicant's priorapplications. Further, the removable midsole orthotic of the presentinvention may be provided as a replacement for worn shoe portions and/orto customize the shoe design for a particular wearer, for a particularactivity or both and, as such, may also be combined with one or more ofthe features or concepts disclosed in my prior applications.

These and other features of the invention will become apparent from thedetailed description of the invention which follows.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1-10 and 12-75 represent embodiments similar to those disclosed inapplicant's issued U.S. patents and previous applications. FIG. 11illustrates aspects of the concavely rounded insertable orthoticmidsoles and compartments or bladders with microprocessor controlledvariable pressure of the of the present invention.

FIG. 1 is a perspective view of a prior art conventional athletic shoeto which the present invention is applicable.

FIG. 2 illustrates in a close-up frontal plane cross section of the heelat the ankle joint the typical shoe known in the art, which does notdeform as a result of body weight, when tilted sideways on the bottomedge.

FIG. 3 shows, in the same close-up cross section as FIG. 2, a naturallyrounded shoe sole design, also tilted sideways.

FIG. 4 shows a rear view of a barefoot heel tilted laterally 20 degrees.

FIG. 5 shows, in a frontal plane cross section at the ankle joint areaof the heel, tension stabilized sides applied to a naturally roundedshoe sole.

FIG. 6 shows, in a frontal plane cross section, the FIG. 5 design whentilted to its edge, but undeformed by load.

FIG. 7 shows, in frontal plane cross section at the ankle joint area ofthe heel, the FIG. 5 design when tilted to its edge and naturallydeformed by body weight.

FIG. 8 is a sequential series of frontal plane cross sections of thebarefoot heel at the ankle joint area.

FIG. 8A is an unloaded and upright barefoot heel.

FIG. 8B is a heel moderately loaded by full body weight and upright.

FIG. 8C is a heavily loaded heel at peak landing force while running andupright.

FIG. 8D is heavily loaded heel shown tilted out laterally by about 20degrees, the maximum tilt for the heel.

FIG. 9 shows a sequential series of frontal plane cross sections of ashoe sole design of the heel at the ankle joint area that correspondsexactly to the FIG. 8 series described above.

FIG. 10 shows two perspective views and a close-up view of a part of ashoe sole with a structure like the fibrous connective tissue of thegroups of fat cells of the human heel.

FIG. 10A shows a quartered section of a shoe sole with a structurecomprising elements corresponding to the calcaneus with fat pad chambersbelow it.

FIG. 10B shows a horizontal plane close-up of the inner structures of anindividual chamber of a shoe sole.

FIG. 10C shows a horizontal section of a shoe sole with a structurecorresponding to the whorl arrangement of fat pad underneath thecalcaneus.

FIGS. 11A-11C are frontal plane cross-sectional views showing threedifferent variations of insertable orthotic midsoles in accordance withthe present invention.

FIG. 11D is an exploded view of an embodiment of an insertable orthoticmidsole in accordance with the present invention.

FIGS. 11E-11F are cross-sectional views of alternative embodiments ofinterlocking interfaces for releasably securing the insertable orthoticmidsole of the present invention.

FIG. 11G is a frontal plane cross-section of an insertable orthoticmidsole formed with asymmetric side height. FIGS. 11H-11J show otherfrontal plane sections. FIG. 11K shows a sagittal plane section and FIG.11L shows a horizontal plane top view.

FIG. 11M-11O are frontal plane cross-sectional views showing threevariations of insertable midsole orthotics with one or more pressurecontrolled encapsulated insertable midsole orthotics and a controlsystem such as a microprocessor.

FIG. 11P is an exploded view of an embodiment of a removable insertablemidsole orthotic with pressure controlled encapsulated midsole sectionsand a control system such as a microprocessor.

FIGS. 11Q-11R are frontal plane cross-sectional views showing twovariations of orthotic inner shoes in accordance with the presentinvention.

FIG. 11S is a cross-sectional view of an embodiment of an interface forincreasing the stability of the insertable orthotic midsole of thepresent invention

FIGS. 12A-12C show a series of conventional shoe sole cross sections inthe frontal plane at the heel utilizing both sagittal plane andhorizontal plane sipes, and in which some or all of the sipes do notoriginate from any outer shoe sole surface, but rather are entirelyinternal

FIG. 12D shows a similar approach as is shown in FIGS. 12A-12C appliedto the fully rounded design.

FIGS. 13A-13B show, in frontal plane cross section at the heel area,shoe sole structures similar to those shown in FIGS. 5A-B, but in moredetail and with the bottom sole extending relatively farther up the sideof the midsole.

FIG. 14 shows, in frontal plane cross section at the heel portion of ashoe, a shoe sole with naturally rounded sides based on a TheoreticallyIdeal Stability Plane.

FIG. 15 shows, in frontal plane cross section, the most general case ofa fully rounded shoe sole that follows the natural rounded of the bottomof the foot as well as its sides, also based on the Theoretically IdealStability Plane.

FIGS. 16A-16C show, in frontal plane cross section at the heel, aquadrant-sided shoe sole, based on a Theoretically Ideal StabilityPlane.

FIG. 17 shows a frontal plane cross section at the heel portion of ashoe with naturally rounded sides like those of FIG. 14, wherein aportion of the shoe sole thickness is increased beyond the TheoreticallyIdeal Stability Plane.

FIG. 18 is a view similar to FIG. 17, but of a shoe with fully roundedsides wherein the sole thickness increases with increasing distance fromthe center line of the ground-contacting portion of the sole.

FIG. 19 is a view similar to FIG. 18 where the fully rounded solethickness variations are continually increasing on each side.

FIG. 20 is a view similar to FIGS. 17-19 wherein the sole thicknessvaries in diverse sequences.

FIG. 21 is a frontal plane cross section showing a density variation inthe midsole.

FIG. 22 is a view similar to FIG. 21 wherein the firmest densitymaterial is at the outermost edge of the midsole rounded.

FIG. 23 is a view similar to FIGS. 21 and 22 showing still anotherdensity variation, one which is asymmetrical.

FIG. 24 shows a variation in the thickness of the sole for thequadrant-sided shoe sole embodiment of FIGS. 16A-16C which is greaterthan a Theoretically Ideal Stability Plane.

FIG. 25 shows a quadrant-sided embodiment as in FIG. 24 wherein thedensity of the sole varies.

FIG. 26 shows a bottom sole tread design that provides a similar densityvariation to that shown in FIG. 23.

FIG. 27 shows embodiments similar to those shown in FIGS. 14-16, butwherein a portion of the shoe sole thickness is decreased to less thanthe Theoretically Ideal Stability Plane.

FIG. 28 shows embodiments of the invention with shoe sole sides havingthicknesses both greater and lesser than the Theoretically IdealStability Plane.

FIG. 29 is a frontal plane cross-section showing a shoe sole of uniformthickness that conforms to the natural shape of the human foot.

FIGS. 30A-30D show a load-bearing flat component of a shoe sole and anaturally rounded side component, as well as a preferred horizontalperiphery of the flat load-bearing portion of the shoe sole.

FIGS. 31A-31B are diagrammatic sketches showing a rounded side soledesign according to the invention with variable heel lift.

FIG. 32 is a side view of a stable rounded shoe according to theinvention.

FIG. 33A is a cross-sectional view of the forefoot portion of a shoesole taken along lines 33A of FIGS. 32 and 33D.

FIG. 33B is a cross-sectional view taken along lines 33B of FIGS. 32 and33D.

FIG. 33C is a cross-sectional view of the heel portion taken along lines33C in FIGS. 32 and 33D.

FIG. 33D is a top view of the shoe sole shown in FIG. 32

FIGS. 34A-34D are frontal plane cross-sectional views of a shoe soleaccording to the invention showing a Theoretically Ideal Stability Planeand truncations of the sole side rounded to reduce shoe bulk.

FIGS. 35A-35C show a rounded sole design according to the invention whenapplied to various tread and cleat patterns.

FIG. 36 is a diagrammatic frontal plane cross-sectional view of staticforces acting on the ankle joint and its position relative to a shoesole according to the invention during normal and extreme inversion andeversion motion.

FIG. 37 is a diagrammatic frontal plane view of a plurality of momentcurves of the center of gravity for various degrees of inversion for ashoe sole according to the invention contrasted with comparable motionsof conventional shoes.

FIG. 38 shows a design with naturally rounded sides extended to otherstructural contours underneath the load-bearing foot such as the mainlongitudinal arch.

FIG. 39 illustrates a fully rounded shoe sole design extended to thebottom of the entire non-load bearing foot.

FIG. 40 shows a fully rounded shoe sole design abbreviated along thesides to only essential structural support and propulsion elements.

FIG. 41 illustrates a street shoe with a correctly rounded soleaccording to the invention and side edges perpendicular to the ground.

FIG. 42 shows several embodiments wherein the bottom sole includes mostor all of the special contours of the designs and retains a flat uppersurface.

FIG. 43 is a rear view of a heel of a foot for explaining the use of astationary sprain simulation test.

FIG. 44 is a rear view of a conventional athletic shoe rotating in anunstable manner about an edge of its sole when the shoe sole is tiltedto the outside.

FIGS. 45A-45C illustrate functionally the principles of naturaldeformation as applied to the shoe soles of the invention.

FIG. 46 shows variations in the relative density of the shoe soleincluding the shoe insole to maximize an ability of the sole to deformnaturally.

FIG. 47 shows a shoe having naturally rounded sides bent inwardly from aconventional design so then when worn the shoe approximates a customfit.

FIG. 48 shows a shoe sole having a fully rounded design but having sideswhich are abbreviated to the essential structural stability andpropulsion elements and are combined and integrated into discontinuousstructural elements underneath the foot that simulate those of the foot.

FIG. 49 shows the Theoretically Ideal Stability Plane concept applied toa negative heel shoe sole that is less thick in the heel area than inthe rest of the shoe sole.

FIG. 49A is a cross sectional view of the forefoot portion taken alongline 49A of FIG. 49D.

FIG. 49B is a view taken along line 49B of FIG. 49D.

FIG. 49C is a view of the heel along line 49C of FIG. 49D.

FIG. 49D is a top view of the shoe sole with a thicker forefoot sectionshown with cross-hatching.

FIGS. 50A-50E show a plurality of side sagittal plane cross sectionalviews of examples of negative heel sole thickness variations (forefootlift) to which the general approach shown in FIGS. 49A-49D can beapplied.

FIG. 51 shows the use of the Theoretically Ideal Stability Plane conceptapplied to a flat shoe sole with no heel lift by maintaining the samethickness throughout and providing the shoe sole with rounded stabilitysides abbreviated to only essential structural support elements.

FIG. 51A is a cross sectional view of the forefoot portion taken alongline 51A of FIG. 51D.

FIG. 51B is a view taken along line 51B of FIG. 51D.

FIG. 51C is a view taken along the heel along line 51C in FIG. 51D.

FIG. 51D is a top view of the shoe sole with sides that are abbreviatedto essential structural support elements shown hatched.

FIG. 51E is a sagittal plane cross section of the shoe sole of FIG. 51D.

FIG. 52 shows, in frontal plane cross section at the heel, the use of ahigh density (d′) midsole material on the naturally rounded sides and alow density (d) midsole material everywhere else to reduce side width.

FIG. 53 shows the footprints of the natural barefoot sole and shoe sole.

FIG. 53A shows the foot upright with its sole flat on the ground.

FIG. 53B shows the foot tilted out 20 degrees to about its normal limit.

FIG. 53C shows a shoe sole of the same size when tilted out 20 degreesto the same position as FIG. 53B. The right foot and shoe are shown.

FIG. 54 shows footprints like those shown in FIGS. 53A and 53B of aright bare foot upright and tilted out 20 degrees, but showing alsotheir actual relative positions to each other as a high arched footrolls outward from upright to tilted out 20 degrees.

FIG. 55 shows a shoe sole with a lateral stability sipe in the form of avertical slit.

FIG. 55A is a top view of a conventional shoe sole with a correspondingoutline of the wearer's footprint superimposed on it to identify theposition of the lateral stability sipe relative to the wearer's foot.

FIG. 55B is a cross section of the shoe sole with lateral stabilitysipe.

FIG. 55C is a top view like FIG. 55A, but showing the print of the shoesole with a lateral stability sipe when it is tilted outward 20 degrees.

FIG. 56 shows a medial stability sipe that is analogous to the lateralsipe, but to provide increased pronation stability. The head of thefirst metatarsal and the first phalange are included with the heel toform a medial support section.

FIG. 57 shows footprints 37 and 17, like FIG. 54, of a right bare footupright and tilted out 20 degrees, showing the actual relative positionsto each other as a low arched foot rolls outward from upright to tiltedout 20 degrees.

FIG. 58A-D show the use of flexible and relatively inelastic fiber inthe form of strands, woven or unwoven (such as pressed sheets), embeddedin midsole and bottom sole material.

FIG. 59A-D show the use of flexible inelastic fiber or fiber strands,woven or unwoven (such as pressed) to make an embedded capsule shellthat surrounds the cushioning compartment 161 containing apressure-transmitting medium like gas, gel, or liquid.

FIG. 60A-D show the use of embedded flexible inelastic fiber or fiberstrands, woven or unwoven, in various embodiments similar those shown inFIGS. 58A-D.

FIG. 60E shows a frontal plane cross section of a fibrous capsule shell191 that directly envelops the surface of the insertable midsoleorthotic 145.

FIG. 61 shows a view of a bottom sole structure 149, but with no sidesections.

FIG. 62 shows a similar structure to FIG. 61, but with only the sectionunder the forefoot 126 unglued or not firmly attached, the rest of thebottom sole 149 (or most of it) would be glued or firmly attached.

FIG. 63C compares the footprint made by a conventional shoe 35 with therelative positions of the wearer's right foot sole in the maximumsupination position 37 a and the maximum pronation position 37 b.

FIG. 63D shows an overhead perspective of the actual bone structures ofthe foot that are indicated in FIG. 63C.

FIG. 64 shows on the right side an upper shoe sole surface of therounded side that is complementary to the shape of the wearer's footsole; on the left side

FIG. 64 shows an upper surface between complementary and parallel to theflat ground and a lower surface of the rounded shoe sole side that isnot in contact with the ground.

FIG. 65 indicates the angular measurements of the rounded shoe solesides from zero degrees to 180 degrees.

FIG. 66 shows a shoe sole without rounded stability sides.

FIGS. 67-68 also shows a shoe sole without rounded stability sides.

FIGS. 69A-E show the implications of relative difference in range ofmotions between forefoot, midtarsal, and heel areas on the applicant'snaturally rounded sides invention.

FIG. 70 shows an invention for a shoe sole that covers the full range ofmotion of the wearer's right foot sole.

FIG. 71 shows an electronic image of the relative forces present at thedifferent areas of the bare foot sole when at the maximum supinationposition shown as 37 a in FIG. 62; the forces were measured during astanding simulation of the most common ankle spraining position.

FIGS. 72G-H show shoe soles with only one or more of the essentialstability elements, but which, based on FIG. 71, still represent majorstability improvements over existing footwear. All omit changes in theheel area.

FIG. 72G shows a shoe sole combining additional stability corrections 96a, 96 b, and 98, supporting the first and fifth metatarsal heads anddistal phalange heads.

FIG. 72H shows a shoe sole with symmetrical stability additions 96 a and96 b.

FIGS. 73A-73D show in close-up sections of the shoe sole various newforms of sipes, including both slits and channels.

FIG. 74 shows, in FIGS. 74A-74E, a plurality of side sagittal planecross-sectional views showing examples of variations in heel liftthickness similar to those shown in FIGS. 50A-E for the forefoot lift.

FIG. 75 shows, in FIGS. 75A-75C, a method for assembling the midsoleshoe sole structure of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to the provision of an insertable midsoleorthotic for a shoe sole which is formed at least in part by midsolematerial and may be removable from the shoe. The insertable midsoleorthotic of the present invention is described more fully with referenceto FIGS. 11A-11P below.

The insertable midsole orthotic, can be used in combination with, or toreplace, any one or more features of the applicant's prior inventions asshown in the figures of this application. Such use of the insertablemidsole orthotic can also include a combination of features shown in anyother figures of the present application. For example, the insertablemidsole orthotic of the present invention may replace all or any portionor portions of the various midsoles, insoles and bottom soles which areshown in the figures of the present application, and may be combinedwith or used to implement one or more of the various other featuresdescribed in reference to any of these figures in any of these forms.

All reference numerals used in the figures contained herein are definedas follows: Ref. No. Element Description  2 insole  3 attachment pointof upper midsole and shoe upper  4 attachment point of bottom sole andshoe upper  5 attachment point of bottom sole and upper midsole  6attachment point of bottom sole and lower midsole  8 lower surfaceinterface with the upper surface of the bottom sole  9 interface linebetween encapsulated section and midsole sections  11 lateral stabilitysipe  12 medial stability sipe  13 interface between insole and shoeupper  14 medial origin of the lateral stability sipe  16 hatched areaof decreased area of footprint due to pronation  17 footprint outlinewhen tilted  18 inner footprint outline of low arched foot  19 hatchedarea of increased area of footprint due to pronation  20 athletic shoe 21 shoe upper  21a inner secondary shoe upper  22 conventional shoesole  23 bottom outside edge of the shoe sole  23a lever arm  26stabilizing quadrants  27 human foot  28 rounded shoe sole  28a roundedstability sides  28b load bearing shoe sole  29 outer surface of thefoot  30 upper surface of the shoe sole  30a side or inner edge of theshoe sole stability side  30b upper shoe sole surface which contacts thewearer's foot  31 lower surface of the shoe sole  31a outer edge ofrounded stability sides  31b lower surface of shoe sole parallel to 30b 32 outside and top edge of the stability side  33 inner edge of thenaturally rounded stability side  34 perpendicular sides of theload-bearing shoe sole  35 peripheral extent of the upper surface ofsole  36 shoe sole outline  37 foot outline  37a maximum supinationposition  37b maximum pronation position  38 heel lift  39 combinedmidsole and bottom sole  40 forefoot lift  43 ground  51 TheoreticallyIdeal Stability Plane  51′ half of the Theoretically Ideal StabilityPlane  53a top of rounded stability side  60 tread portion  61 cleatedportion  62 alternative tread construction  63 surface which the cleatbases are affixed  70 curve of range of side to side motion  71 centerof gravity  80 conventional wide heel flare curve  82 narrow rectanglethe width of heel curve  85 rounded line of areas of shoe sole that arein contact with the ground  86 rounded line  86 rounded line  87 roundedline  88 rounded line  89 rounded line  92 head of first metatarsal  93head of fifth distal phalange  94 head of fifth metatarsal  95 base andlateral tuberosity of the calcaneus  96 heads of the metatarsals  96astability correction supporting fifth metatarsal and distal phalangeheads  96b stability correction supporting first metatarsal and distal  phalange heads  97 base of the fifth metatarsal  98 head of the firstdistal phalange  98a stability correction supporting first distalphalange  98a′ stability correction supporting fifth distal phalange 100straight line replacing indentation at the base of the fifth metatarsal104 pressure sensing device 108 lateral calcaneal tuberosity 109 mainbase of the calcaneus 111 flexibility axis 112 flexibility axis 113flexibility axis 115 center of rotation of radius r + r′ 119 center ofshoe sole support section 120 pressure sensing circuitry 121 mainlongitudinal arch (long arch) 122 flexibility axis 123 flexibleconnecting top layer of sipes 124 flexibility axis 125 base of thecalcaneus (heel) 126 metatarsal heads (forefoot) 129 honeycombed portion145 insertable midsole orthotic 147 upper midsole (upper areas of shoemidsole) 148 midsole 149 bottom or outer sole 149a secondary bottom sole150 compression force 151 channels with parallel side walls 155a tensionforce along the top surface of the shoe sole 155b mirror image oftension force 155a 158 subcalcaneal fat pad 159 calcaneus 160 bottomsole of the foot 161 cushioning compartment 162 natural crease or upwardtaper 163 crease or taper in the human foot 164 chambers of matrix ofelastic fibrous connective tissue 165 lower surface of the upper midsole166 upper surface of the bottom sole 167 outer surface of the supportstructures of the foot 168 upper surface of the foot's bottom sole 169shank 170 flexible material filling channels (sipes) 180 mini-chambers181 internal deformation slits (sipes) in the sagittal plane 182internal deformation slits (sipes) in the horizontal plane 184encapsulating outer midsole section 185 midsole sides 187 upper midsolesection 188 bladder or encapsulated midsole section 189 central wall 191fibrous capsule shell 192 subdivided cushioning compartments 201horizontal line through lower most point of upper surface of the shoesole 206 fluid duct 210 fluid valve 300 encapsulated midsole sectioncontrol system

FIG. 1 shows a perspective view of a shoe, such as a typical athleticshoe according to the prior art, wherein the athletic shoe 20 includesan upper portion 21 and a sole 22.

FIG. 2 illustrates, in a close-up, a cross-section of a typical shoe ofexisting art (undeformed by body weight) on the ground 43 when tilted onthe bottom outside edge 23 of the shoe sole 22, that an inherentstability problem remains in existing shoe designs, even when theabnormal torque producing rigid heel counter and other motion devicesare removed. The problem is that the remaining shoe upper 21 (shown inthe thickened and darkened line), while providing no lever armextension, since it is flexible instead of rigid, nonetheless createsunnatural destabilizing torque on the shoe sole. The torque is due tothe tension force 155 a along the top surface of the shoe sole 22 causedby a compression force 150 (a composite of the force of gravity on thebody and a sideways motion force) to the side by the foot 27, due simplyto the shoe being tilted to the side, for example. The resultingdestabilizing force acts to pull the shoe sole in rotation around alever arm 23 a that is the width of the shoe sole at the edge. Roughlyspeaking, the force of the foot on the shoe upper pulls the shoe over onits side when the shoe is tilted sideways. The compression force 150also creates a tension force 155 b, which is the mirror image of tensionforce 155 a.

FIG. 3 shows, in a close-up cross section of a naturally rounded designshoe sole 28 (also shown undeformed by body weight) when tilted on thebottom edge, that the same inherent stability problem remains in thenaturally rounded shoe sole design, though to a reduced degree. Theproblem is less since the direction of the force vector 150 along thelower surface of the shoe upper 21 is parallel to the ground 43 at theouter sole edge 32 edge, instead of angled toward the ground as in aconventional design like that shown in FIG. 2, so the resulting torqueproduced by a lever arm created by the outer sole edge 32 would be less,and the rounded shoe sole 28 provides direct structural support whentilted, unlike conventional designs.

FIG. 4 shows (in a rear view) that, in contrast, the bare foot isnaturally stable because, when deformed by body weight and tilted to itsnatural lateral limit of about 20 degrees, it does not create anydestabilizing torque due to tension force. Even though tensionparalleling that on the shoe upper is created on the outer surface 29,both the bottom and sides, of the bare foot by the compression force ofweight-bearing, no destabilizing torque is created because the lowersurface under tension (i.e. the foot's bottom sole, shown in thedarkened line) is resting directly in contact with the ground.Consequently, there is no unnatural lever arm artificially createdagainst which to pull. The weight of the body firmly anchors the outersurface of the sole underneath the foot so that even considerablepressure against the outer surface 29 of the side of the foot results inno destabilizing motion. When the foot is tilted, the supportingstructures of the foot, like the calcaneus, slide against the side ofthe strong but flexible outer surface of the foot and create verysubstantial pressure on that outer surface at the sides of the foot. Butthat pressure is precisely resisted and balanced by tension along theouter surface of the foot, resulting in a stable equilibrium.

FIG. 5 shows, in cross section of the upright heel deformed by bodyweight, the principle of the tension-stabilized sides of the bare footapplied to the naturally rounded shoe sole design. The same principlecan be applied to conventional shoes, but is not shown. The key changefrom the existing art of shoes is that the sides of the shoe upper 21(shown as darkened lines) must wrap around the outside edges 32 of therounded shoe sole 28, instead of attaching underneath the foot to theupper surface 30 of the shoe sole, as is done conventionally. The shoeupper sides can overlap and be attached to either the inner (shown onthe left) or outer surface (shown on the right) of the bottom sole,since those sides are not unusually load-bearing, as shown.Alternatively, the bottom sole, optimally thin and tapering as shown,can extend upward around the outside edges 32 of the shoe sole tooverlap and attach to the shoe upper sides (shown FIG. 5B). Theiroptimal position coincides with the Theoretically Ideal Stability Plane,so that the tension force on the shoe sides is transmitted directly allthe way down to the bottom surface of the shoe, which anchors it on theground with virtually no intervening artificial lever arm. For shoeswith only one sole layer, the attachment of the shoe upper sides shouldbe at or near the lower or bottom surface of the shoe sole.

The design shown in FIG. 5 is based on a fundamentally differentconception: that the shoe upper is integrated into the shoe sole,instead of attached on top of it, and the shoe sole is treated as anatural extension of the foot sole, not attached to it separately.

The fabric (or other flexible material, like leather) of the shoe upperswould preferably be non-stretch or relatively so, so as not to bedeformed excessively by the tension placed upon its sides whencompressed as the foot and shoe tilt. The fabric can be reinforced inareas of particularly high tension, like the essential structuralsupport and propulsion elements defined in the applicant's earlierapplications (the base and lateral tuberosity of the calcaneus, the baseof the fifth metatarsal, the heads of the metatarsals, and the firstdistal phalange). The reinforcement can take many forms, such as likethat of comers of the jib sail of a racing sailboat or more simplestraps. As closely as possible, it should have the same performancecharacteristics as the heavily callused skin of the sole of anhabitually bare foot. Preferably, the relative density of the shoe soleis as described in FIG. 46 of the present application with the softestsole density nearest the foot sole, a progression through less soft soledensity through the sole, to the firmest and least flexible at theoutermost shoe sole layer. This arrangement allows the conforming sidesof the shoe sole to avoid providing a rigid destabilizing lever arm.

The change from existing art to provide the tension-stabilized sidesshown in FIG. 5 is that the shoe upper is directly integratedfunctionally with the shoe sole, instead of simply being attached on topof it. The advantage of the tension-stabilized sides design is that itprovides natural stability as close to that of the bare foot aspossible, and does so economically, with the minimum shoe sole sidewidth possible.

The result is a shoe sole that is naturally stabilized in the same waythat the barefoot is stabilized, as seen in FIG. 6, which shows aclose-up cross section of a naturally rounded shoe sole 28 (undeformedby body weight) when tilted to the edge. The same destabilizing forceagainst the side of the shoe shown in FIG. 2 is now stably resisted byoffsetting tension in the surface of the shoe upper 21 extended down theside of the shoe sole so that it is anchored by the weight of the bodywhen the shoe and foot are tilted.

In order to avoid creating unnatural torque on the shoe sole, the shoeuppers may be joined or bonded only to the bottom sole, not the midsole,so that pressure shown on the side of the shoe upper produces sidetension only and not the destabilizing torque from pulling similar tothat described in FIG. 2. However, to avoid unnatural torque, the upperareas 147 of the shoe midsole, which form a sharp corner, should becomposed of relatively soft midsole material. In this case, bonding theshoe uppers to the midsole would not create very much destabilizingtorque. The bottom sole 149 is preferably thin, at least on thestability sides, so that its attachment overlap with the shoe uppersides coincides, as closely as possible, to the Theoretically IdealStability Plane, so that force is transmitted by the outer shoe solesurface to the ground.

In summary, the FIG. 5 design is for a shoe construction, including: ashoe upper that is composed of material that is flexible and relativelyinelastic at least where the shoe upper contacts the areas of thestructural bone elements of the human foot, and a shoe sole that hasrelatively flexible sides; and at least a portion of the sides of theshoe upper are attached directly to the bottom sole, while enveloping onthe outside the other sole portions of the shoe sole. This constructioncan either be applied to conventional shoe sole structures or to theapplicant's prior shoe sole inventions, such as the naturally roundedshoe sole conforming to the Theoretically Ideal Stability Plane.

FIG. 7 shows, in cross-section at the heel, the tension-stabilized sidesconcept applied to naturally rounded shoe sole 28 when the shoe and footare tilted out fully and are naturally deformed by body weight (althoughconstant shoe sole thickness is shown undeformed). The figure shows thatthe shape and stability function of the shoe sole and shoe uppers mirroralmost exactly that of the human foot.

FIGS. 8A-8D show the natural cushioning of the human bare foot 27, incross sections at the heel. FIG. 8A shows the bare heel upright andunloaded, with little pressure on the subcalcaneal fat pad 158, which isevenly distributed between the calcaneus 159, which is the heel bone,and the bottom sole 160 of the foot.

FIG. 8B shows the bare heel upright but under the moderate pressure offull body weight. The compression of the calcaneus against thesubcalcaneal fat pad produces evenly balanced pressure within thesubcalcaneal fat pad because it is contained and surrounded by arelatively unstretchable fibrous capsule, the bottom sole of the foot.Underneath the foot, where the bottom sole is in direct contact with theground, the pressure caused by the calcaneus on the compressedsubcalcaneal fat pad is transmitted directly to the ground.Simultaneously, substantial tension is created on the sides of thebottom sole of the foot because of the surrounding relatively toughfibrous capsule. That combination of bottom pressure and side tension isthe foot's natural shock absorption system for support structures likethe calcaneus and the other bones of the foot that come in contact withthe ground.

Of equal functional importance is that lower surface 167 of thosesupport structures of the foot like the calcaneus and other bones makefirm contact with the upper surface 168 of the foot's bottom soleunderneath, with relatively little uncompressed fat pad intervening. Ineffect, the support structures of the foot land on the ground and arefirmly supported; they are not suspended on top of springy material in abuoyant manner analogous to a water bed or pneumatic tire, as in someexisting proprietary shoe sole cushioning systems. This simultaneouslyfirm and yet cushioned support provided by the foot sole must have asignificantly beneficial impact on energy efficiency, also called energyreturn, different from some conventional shoe sole designs which provideshock absorption cushioning during the landing and support phases oflocomotion at the expense of firm support during the take-off phase.

The incredible and unique feature of the foot's natural system is that,once the calcaneus is in fairly direct contact with the bottom sole andtherefore providing firm support and stability, increased pressureproduces a more rigid fibrous capsule that protects the calcaneus andproduces greater tension at the sides to absorb shock. So, in a sense,even when the foot's suspension system would seem in a conventional wayto have bottomed out under normal body weight pressure, it continues toreact with a mechanism to protect and cushion the foot even under verymuch more extreme pressure. This is seen in FIG. 8C, which shows thehuman heel under the heavy pressure of roughly three times body weightforce of landing during routine running. This can be easily verified:when one stands barefoot on a hard floor, the heel feels very firmlysupported and yet can be lifted and virtually slammed onto the floorwith little increase in the feeling of firmness; the heel simply becomesharder as the pressure increases.

In addition, it should be noted that this system allows the relativelynarrow base of the calcaneus to pivot from side to side freely in normalpronation/supination motion, without any obstructing torsion on it,despite the very much greater width of compressed foot sole providingprotection and cushioning. This is crucially important in maintainingnatural alignment of joints above the ankle joint such as the knee, hipand back, particularly in the horizontal plane, so that the entire bodyis properly adjusted to absorb shock correctly. In contrast, existingshoe sole designs, which are generally relatively wide to providestability, produce unnatural frontal plane torsion on the calcaneus,restricting its natural motion, and causing misalignment of the jointsoperating above it, resulting in the overuse injuries unusually commonwith such shoes. Instead of flexible sides that harden under tensioncaused by pressure like that of the foot, some existing shoe soledesigns are forced by lack of other alternatives to use relatively rigidsides in an attempt to provide sufficient stability to offset theotherwise uncontrollable buoyancy and lack of firm support of air or gelcushions.

FIG. 8D shows the bare foot deformed under full body weight and tiltedlaterally to roughly the 20 degree limit of normal movement range. Againit is clear that the natural system provides both firm lateral supportand stability by providing relatively direct contact with the ground,while at the same time providing a cushioning mechanism through sidetension and subcalcaneal fat pad pressure.

FIGS. 9A-9D show, also in cross-sections at the heel, a naturallyrounded shoe sole design that parallels as closely as possible theoverall natural cushioning and stability system of the barefootdescribed in FIG. 8, including a cushioning compartment 161 undersupport structures of the foot containing a pressure-transmitting mediumlike gas, gel, or liquid, like the subcalcaneal fat pad under thecalcaneus and other bones of the foot. Consequently, FIGS. 9A-D directlycorrespond to FIGS. 8A-D. The optimal pressure-transmitting medium isthat which most closely approximates the fat pads of the foot. Siliconegel is probably most optimal of materials currently readily available,but future improvements are probable. Since it transmits pressureindirectly, in that it compresses in volume under pressure, gas issignificantly less optimal. The gas, gel, or liquid, or any othereffective material, can be further encapsulated itself, in addition tothe sides of the shoe sole, to control leakage and maintain uniformity,as is common conventionally, and can be subdivided into any practicalnumber of encapsulated areas within a compartment, again as is commonconventionally. The relative thickness of the cushioning compartment 161can vary, as can the bottom sole 149 and the upper midsole 147, and canbe consistent or differ in various areas of the shoe sole. The optimalrelative sizes should be those that approximate most closely those ofthe average human foot, which suggests both smaller upper and lowersoles and a larger cushioning compartment than shown in FIG. 9. Thecushioning compartments or pads 161 can be placed anywhere from directlyunderneath the foot, like an insole, to directly above the bottom sole.Optimally, the amount of compression created by a given load in anycushioning compartment 161 should be tuned to approximate as closely aspossible the compression under the corresponding fat pad of the foot.

The function of the subcalcaneal fat pad is not met satisfactorily withexisting proprietary cushioning systems, even those featuring gas, gelor liquid as a pressure transmitting medium. In contrast to thoseartificial systems, the design shown in FIG. 9 conforms to the naturalrounded of the foot and to the natural method of transmitting bottompressure into side tension in the flexible but relatively non-stretching(the actual optimal elasticity will require empirical studies) sides ofthe shoe sole.

Some existing cushioning systems do not bottom out under moderate loadsand rarely if ever do so under extreme loads. Rather, the upper surfaceof the cushioning device remains suspended above the lower surface. Incontrast, the design in FIG. 9 provides firm support to foot supportstructures by providing for actual contact between the lower surface 165of the upper midsole 147 and the upper surface 166 of the bottom sole149 when fully loaded under moderate body weight pressure, as indicatedin FIG. 9B, or under maximum normal peak landing force during running,as indicated in FIG. 9C, just as the human foot does in FIGS. 8B and 8C.The greater the downward force transmitted through the foot to the shoe,the greater the compression pressure in the cushioning compartment 161and the greater the resulting tension on the shoe sole sides.

FIG. 9D shows the same shoe sole design when fully loaded and tilted tothe natural 20 degree lateral limit, like FIG. 8D. FIG. 9D shows that anadded stability benefit of the natural cushioning system for shoe solesis that the effective thickness of the shoe sole is reduced bycompression on the side so that the potential destabilizing lever armrepresented by the shoe sole thickness is also reduced, and thus footand ankle stability is increased. Another benefit of the FIG. 9 designis that the upper midsole shoe surface can move in any horizontaldirection, either sideways or front to back in order to absorb shearingforces. The shearing motion is controlled by tension in the sides. Notethat the right side of FIGS. 9A-D is modified to provide a naturalcrease or upward taper 162, which allows complete side compressionwithout binding or bunching between the upper and lower shoe sole layers147, 148, and 149. The shoe sole crease 162 parallels exactly a similarcrease or taper 163 in the human foot. Further, 201 represents ahorizontal line through the lower most point of the upper surface 30 ofthe shoe sole.

Another possible variation of joining shoe upper to shoe bottom sole ison the right (lateral) side of FIGS. 9A-D, which makes use of the factthat it is optimal for the tension absorbing shoe sole sides, whethershoe upper or bottom sole, to coincide with the Theoretically IdealStability Plane along the side of the shoe sole beyond that pointreached when the shoe is tilted to the foot's natural limit, so that nodestabilizing shoe sole lever arm is created when the shoe is tiltedfully, as in FIG. 9D. The joint may be moved up slightly so that thefabric side does not come in contact with the ground, or it may becovered with a coating to provide both traction and fabric protection.

It should be noted that the FIG. 9 design provides a structural basisfor the shoe sole to conform very easily to the natural shape of thehuman foot and to parallel easily the natural deformation flattening ofthe foot during load-bearing motion on the ground. This is true even ifthe shoe sole is made conventionally with a flat sole, as long as rigidstructures such as heel counters and motion control devices are notused; though not optimal, such a conventional flat shoe made like FIG. 9would provide the essential features of the invention resulting insignificantly improved cushioning and stability. The FIG. 9 design couldalso be applied to intermediate-shaped shoe soles that neither conformto the flat ground or the naturally rounded foot. In addition, the FIG.9 design can be applied to the applicant's other designs, such as thosedescribed in FIGS. 14-28 of the present application.

In summary, the FIG. 9 design shows a shoe construction for a shoe,including: a shoe sole with a compartment or compartments under thestructural elements of the human foot, including at least the heel; thecompartment or compartments contain a pressure-transmitting medium likeliquid, gas, or gel; a portion of the upper surface of the shoe solecompartment firmly contacts the lower surface of said compartment duringnormal load-bearing; and pressure from the load-bearing is transmittedprogressively at least in part to the relatively inelastic sides, topand bottom of the shoe sole compartment or compartments, producingtension.

While the FIG. 9 design copies in a simplified way the macro structureof the foot, FIGS. 10A-C focus more on the exact detail of shoe solesmodeled after the natural structures of the foot, including at the microlevel. FIGS. 10A and 10C are perspective views of cross sections of apart of a rounded shoe sole 28 with a structure like the human heel,wherein elements of the shoe sole structure are similar to chambers of amatrix of elastic fibrous connective tissue which hold closely packedfat cells in the foot 164. The chambers in the foot are structured aswhorls radiating out from the calcaneus. These fibrous-tissue strandsare firmly attached to the under surface of the calcaneus and extend tothe subcutaneous tissues. They are usually in the form of the letter U,with the open end of the U pointing toward the calcaneus.

As the most natural, an approximation of this specific chamber structurewould appear to be the most optimal as an accurate model for thestructure of the shoe sole cushioning compartments 161. The descriptionof the structure of calcaneal padding provided by Erich Blechschmidt inFoot and Ankle, March, 1982, (translated from the original 1933 articlein German) is so detailed and comprehensive that copying the samestructure as a model in shoe sole design is not difficult technically,once the crucial connection is made that such copying of this naturalsystem is necessary to overcome inherent weaknesses in the design ofexisting shoes. Other arrangements and orientations of the whorls arepossible, but would probably be less optimal.

Pursuing this nearly exact design analogy, the lower surface 165 of theupper midsole 147 would correspond to the outer surface 167 of thecalcaneus 159 and would be the origin of the U shaped whorl chambers 164noted above.

FIG. 10B shows a close-up of the interior structure of the largechambers of a rounded shoe sole 28 as shown in FIGS. 10A and 10C, withmini-chambers 180 similar to mini-chambers in the foot. It is clear fromthe fine interior structure and compression characteristics of themini-chambers 180 in the foot that those directly under the calcaneusbecome very hard quite easily, due to the high local pressure on themand the limited degree of their elasticity, so they are able to providevery firm support to the calcaneus or other bones of the foot sole. Byvirtue of their being fairly inelastic, the compression forces on thosecompartments are dissipated to other areas of the network of fat padsunder any given support structure of the foot, like the calcaneus.Consequently, if a cushioning compartment 161, such as the compartmentunder the heel shown in FIG. 9, is subdivided into smaller chambers,like those shown in FIG. 10, then actual contact between the lowersurface of the upper midsole 165 and the upper surface of the bottomsole 166 would no longer be required to provide firm support, so long asthose compartments and the pressure-transmitting medium contained inthem have material characteristics similar to those of the foot, asdescribed above. The use of gas may not be satisfactory in thisapproach, since its compressibility may not allow adequate firmness.

In summary, the FIG. 10 design shows a shoe construction including: ashoe sole with a compartments under the structural elements of the humanfoot, including at least the heel; the compartments containing apressure-transmitting medium like liquid, gas, or gel; the compartmentshaving a whorled structure like that of the fat pads of the human footsole; load-bearing pressure being transmitted progressively at least inpart to the relatively inelastic sides, top and bottom of the shoe solecompartments, producing tension therein; the elasticity of the materialof the compartments and the pressure-transmitting medium are such thatnormal weight-bearing loads produce sufficient tension within thestructure of the compartments to provide adequate structural rigidity toallow firm natural support to the foot structural elements, like thatprovided by the fat pads of the bare foot. That shoe sole constructioncan have shoe sole compartments that are subdivided into mini-chamberslike those of the fat pads of the foot sole.

Since the bare foot that is never shod is protected by very hardcalluses (called a “Seri boot”) which the shod foot lacks, it seemsreasonable to infer that natural protection and shock absorption systemof the shod foot is adversely affected by its unnaturally undevelopedfibrous capsules (surrounding the subcalcaneal and other fat pads underfoot bone support structures). A solution would be to produce a shoeintended for use without socks (i.e. with smooth surfaces above the footbottom sole) that uses insoles that coincide with the foot bottom sole,including its sides. The upper surface of those insoles, which would bein contact with the bottom sole of the foot (and its sides), would becoarse enough to stimulate the production of natural barefoot calluses.The insoles would be removable and available in different uniform gradesof coarseness, as is sandpaper, so that the user can progress from finergrades to coarser grades as his foot soles toughen with use.

Similarly, socks could be produced to serve the same function, with thearea of the sock that corresponds to the foot bottom sole (and sides ofthe bottom sole) made of a material coarse enough to stimulate theproduction of calluses on the bottom sole of the foot, with differentgrades of coarseness available, from fine to coarse, corresponding tofeet from soft to naturally tough. Using a tube sock design with uniformcoarseness, rather than conventional sock design assumed above, wouldallow the user to rotate the sock on his foot to eliminate any “hotspot” irritation points that might develop. Also, since the toes aremost prone to blistering and the heel is most important in shockabsorption, the toe area of the sock could be relatively less abrasivethan the heel area

Orthotics are well known in the art and are exemplified by U.S. Pat. No.4,803,747 issued to Brown and U.S. Pat. No. 4,868,945 issued toDeBettignies.

The invention shown in FIGS. 11A-11C includes a removable, andreinsertable, insertable midsole orthotic 145 which is formed at leastin part by midsole material. Alternatively, the insertable midsoleorthotic 145 can be attached permanently to adjoining portions of therounded shoe sole 28 after initial insertion using glue or other commonforms or attachment. The rounded shoe sole 28 has an upper surface 30and a lower surface 31 with at least a part of both surfaces beingconcavely rounded, as viewed in a frontal plane from inside the shoewhen in an unloaded and upright condition. Preferably, all or a part ofthe insertable midsole orthotic 145 can be removable through anypractical number of insertion/removal cycles. The insertable midsoleorthotic 145 can also, optionally, include a concavely rounded side, asshown in FIG. 11A, or a concavely rounded underneath portion or beconventionally formed, with other portions of the shoe sole includingconcave rounding on the side or underneath portion or portions. All orpart of the preferred insole 2 can also be removable or can beintegrated into the upper portion of the insertable midsole orthotic145.

The removable portion or portions of the insertable midsole orthotic 145can include all or part of the heel lift (not shown) of the rounded shoesole 28, or all or part of the heel lift 38 can be incorporated into thebottom sole 149 permanently, either using bottom sole material, midsolematerial, or other suitable material. Heel lift 38 is typically formedfrom cushioning material such as the midsole materials described hereinor may be integrated with the upper midsole 147 or midsole 148 or anyportion thereof, including the insertable midsole orthotic 145.

The removable portion of the insertable midsole orthotic 145 can extendthe entire length of the shoe sole, as shown in FIGS. 11K and 11L, oronly a part of the length, such as a heel area as shown in cross sectionin FIG. 11G, a midtarsal area as shown in cross section in FIG. 11H, aforefoot area as shown in cross section FIGS. 11I and 11J, or someportion or combination of those areas. The removable portion and/orinsertable midsole orthotic 145 may be fabricated in any suitable,conventional manner employed for the fabrication of midsoles or other,similar structures.

The insertable midsole orthotic 145, as well as other midsole sectionsof the shoe sole such as the midsole 148 and the upper midsole 147, canbe fabricated from any suitable material such as elastomeric foammaterials. Examples of current art for elastomeric foam materialsinclude polyether urethane, polyester urethane foams, ethylene vinylacetate, ethylene vinyl acetate/polyethylene copolymers, polyesterelastomers such as Hytrel® fluoroelastomers, chlorinated polyethylene,chlorosulfonated polyethylene, acrylonitrile rubber, ethylene vinylacetate/polypropylene copolymers, polyethylene, polypropylene, neoprene,natural rubber, Dacron® polyester, polyvinyl chloride, thermoplasticrubbers, nitrile rubber, butyl rubber, sulfide rubber, polyvinylacetate, methyl rubber, buna N, buna S, polystyrene, ethylene propylenepolymers, polybutadiene, butadiene styrene rubber, and silicone rubbers.The most preferred elastomeric foam materials in the current art of theshoe sole midsole materials are polyurethanes, ethylene vinyl acetate,ethylene vinyl acetate/polyethylene copolymers, ethylene vinylacetate/polypropylene copolymers, neoprene and polyester elastomers.Suitable materials are selected on the basis of durability, flexibilityand resiliency for cushioning and supporting the foot, among otherproperties, such as protecting and insulating.

As shown in FIG. 11D, the insertable midsole orthotic 145 itself canincorporate cushioning or structural compartments or components. FIG.11D shows cushioning compartments or chambers 161 encapsulated in partof the insertable midsole orthotic 145, as well as bottom sole 149, asviewed in a frontal plane cross-section. FIG. 11D is a perspective viewindicating the placement of disks or capsules of cushioning material.The disks or capsules of cushioning material may be made from any of themidsole materials mentioned above, and preferably include a flexible,resilient midsole material such as ethyl vinyl acetate (EVA), that maybe softer or firmer than other sole material or may be provided withspecial shock absorption, energy efficiency, wear, or stabilitycharacteristics. The disks or capsules may include a gas, gel, liquid orany other suitable cushioning material. The cushioning material mayoptionally be encapsulated itself using a film made of a suitablematerial such as polyurethane film. Other similar materials may also beemployed. The encapsulation can be used to form the cushioning materialinto an insertable capsule in a conventional manner. The example shownin FIG. 11D shows such cushioning disks 161 located in the heel area andthe lateral and medial forefoot areas, proximate to the heads of thefirst and fifth metatarsal bones of a wearer's foot. The cushioningmaterial, for example disks or compartments 161, may form part of theupper surface of the upper portion of the insertable midsole orthotic145 as shown in FIG. 11D. A cushioning compartment or disk 161 cangenerally be placed anywhere in the insertable midsole orthotic 145 orin only a part of the insertable midsole orthotic 145. A part of thecushioning compartment or disk 161 can extend into the outer sole 149 orother sole portion or, alternatively, one or more compartments or disks161 may constitute all or substantially all of the insertable midsoleorthotic 145. As shown in FIG. 11L, cushioning disks or compartments 161may also be suitably located at other essential support elements likethe base of the fifth metatarsal 97, the head of the first distalphalange 98, or the base and lateral tuberosity of the calcaneus 95,among other suitable conventional locations. In addition, structuralcomponents like a shank 169 can also be incorporated partially orcompletely in an insertable midsole orthotic 145, such as in the medialmidtarsal area, as shown in FIG. 11D, under the main longitudinal archof a wearer's foot, and/or under the base of the wearer's fifthmetatarsal bone, or other suitable alternative locations.

In one embodiment, the FIG. 11D invention can be made of allmass-produced standard size components, rather than custom fit, but canbe individually tailored for the right and left shoe with variations inthe firmness of the material in compartments 161 for specialapplications such as sport shoes, golf shoes or other shoes which mayrequire differences between firmness of the left and right shoe sole.

One of the advantages provided by the insertable midsole orthotic 145 ofthe present invention is that it allows replacement of foamed plasticportions of the midsole which degrade quickly with wear, losing theirdesigned level of resilience, with new midsole material as necessaryover the life of the shoe to thereby maintain substantially optimalshock absorption and energy return characteristics of the rounded shoesole 28.

The insertable midsole orthotic 145 can also be transferred from onepair of shoes composed generally of shoe uppers and bottom sole likeFIG. 11C to another pair like FIG. 11C, providing cost savings.

Besides using the insertable midsole orthotic 145 to replace worncomponents with new components, the replacement insertable midsoleorthotic 145 can provide another advantage of allowing the use ofdifferent cushioning or support characteristics in a single shoe or pairof shoes made like FIG. 11C, such as firmer or softer portions of themidsole or thicker or thinner portions of the midsole, or entiremidsoles that are firmer, softer, thicker or thinner, either as separatelayers or as an integral part of insertable midsole orthotic 145. Inthis manner, a single pair of shoes can be customized to provide thedesired cushioning or support characteristics for a particular activityor different levels of activity, such as running, training or racingshoes. FIG. 11D shows an example of such insertable portions of themidsole in the form of disks or capsules 161, but midsole or insolelayers or the entire midsole section can be removed and replacedtemporarily or permanently.

Such insertable midsole orthotics 145 can be made to include density orfirmness variations like those shown in FIGS. 21-23 and 25. The midsoledensity or firmness variations can differ between a right foot shoe anda left foot shoe, such as FIG. 21 as a left shoe and FIG. 22 as a rightshoe, showing equivalent portions.

Such replacement insertable midsole orthotics 145 can be made to includethickness variations, including those shown in FIGS. 17-20, 24, 27, or28. Combinations of density or firmness variations and thicknessvariations shown above can also be made in the insertable midsoleorthotics 145.

Replacement insertable midsole orthotics 145 may be held in position atleast in part by enveloping sides of the shoe upper 21 and/or bottomsole 149. Alternatively, a portion of the midsole material may be fixedin the shoe sole and extend up the sides to provide support for holdinginsertable midsole orthotics 145 in place. If the associated roundedshoe sole 28 has one or more of the abbreviated sides shown in FIG. 11L,then the insertable midsole orthotic 145 can also be held in positionagainst relative motion in the sagittal plane by indentations formedbetween one or more concavely rounded sides and the adjacentabbreviations. Combinations of these various embodiments may also beemployed.

The insertable midsole orthotic 145 has a lower surface interface 8 withthe upper surface of the bottom sole 149. The interface 8 wouldtypically remain unglued, to facilitate repeated removal of theinsertable midsole orthotic 145, or could be affixed by a weak glue,like that of self-stick removable paper notes, that does not permanentlyfix the position of the insertable midsole orthotic 145 in place.

The interface 8 can also be bounded by non-slip or controlled slippagesurfaces. The two surfaces which form the interface 8 can haveinterlocking complementary geometries as shown, for example, in FIGS.11E-11F, such as mating protrusions and indentations, or the insertablemidsole orthotic 145 may be held in place by other conventionaltemporary attachments, such as, for example Velcro® strips. Conversely,providing no means to restrain slippage between the surfaces ofinterface 8 may, in some cases, provide additional injury protection.Thus, controlled facilitation of slippage at the interface 8 may bedesirable in some instances and can be utilized within the scope of theinvention.

It is presently contemplated that the insertable midsole orthotics 145,particularly including those involving more complex midsole variations,such as those involving material or structural asymmetry between rightand left shoes, would necessarily be prescribed by health careprofessionals, such as podiatrists or orthopedic or other physicians, inorder to provide the maximum benefits and safety of such midsolesections. Such complex midsole variations can also be prescribed forcorrective, therapeutic, prosthetic and other purposes by health careprofessionals.

The insertable midsole orthotic 145 of the present invention may beinserted and removed in the same manner as conventional removableinsoles or conventional midsoles, that is generally in the same manneras the wearer inserts his foot into the shoe. Insertion of theinsertable midsole orthotic 145 may, in some cases, require loosening ofthe shoe laces or other mechanisms for securing the shoe to a wearer'sfoot. For example, the insertable midsole orthotic 145 may be insertedinto the interior cavity of the shoe upper and affixed to or abuttedagainst the top side of the shoe sole 28. In a particularly preferredembodiment, a bottom sole 149 is first inserted into the interior cavityof the shoe upper 21 as indicated by the arrow in FIG. 75A. The bottomsole 149 is inserted into the cavity so that any rounded stability sides28 a are inserted into and protrude out of corresponding openings in theshoe upper 21. The bottom sole 149 is then attached to the shoe upper21, preferably by a stitch that weaves around the outer perimeter of theopenings thereby connecting the shoe upper 21 to the bottom sole 149. Inaddition, an adhesive can be applied to the surface of the shoe upper 21which will contact the bottom sole 149 before the bottom sole 149 isinserted into the shoe upper 21.

Once the bottom sole 149 is attached, the insertable midsole orthotic145 may then be inserted into the interior cavity of the shoe upper 21and affixed to the top side of the bottom sole 149, as shown in FIG.75C. The insertable midsole orthotic 145 can be releasably secured inplace by any suitable method, including mechanical fasteners, adhesives,snap-fit arrangements, reclosable compartments, interlocking geometriesand other similar structures. Additionally, the insertable midsoleorthotic 145 preferably includes protrusions placed in an abuttingrelationship with the bottom sole 149 so that the protrusions occupycorresponding recesses in the bottom sole 149.

Alternatively, the insertable midsole orthotic 145 may be glued to affixthe insertable midsole orthotic 145 in place on the bottom sole 149. Insuch an embodiment, an adhesive can be used on the bottom side of theinsertable midsole orthotic 145 to secure the midsole to the bottom sole149.

Replacement insertable midsole orthotics 145 with concavely roundedsides that provide support for only a narrow range of sideways motion orwith higher concavely rounded sides that provide for a very wide rangeof sideways motion can be used to adapt the same shoe for differentsports, like running or basketball, for which lessor or greaterprotection against ankle sprains may be considered necessary, as shownin FIG. 11G. Different insertable midsole orthotics 145 may also beemployed on the left or right side, respectively. Replacement insertablemidsole orthotics 145 with higher curved sides that provide for an extrarange of motion for sports which tend to encourage pronation-pronewearers on the medial side, or on the lateral side for sports which tendto encourage supination-prone wearers are other potentially beneficialembodiments.

Individual insertable midsole orthotics 145 can be custom made for aspecific class of wearer or can be selected by the health professionalfrom mass-produced standard sizes with standard variations in the heightof the concavely rounded sides, for example.

FIGS. 11M-11P show shoe soles with one or more encapsulated midsolesections or chambers such as bladders 188 for containing fluid such as agas, liquid, gel or other suitable materials, and with a duct, a flowregulator, a sensor, and a control system such as a microcomputer. Theexisting art is described by U.S. Pat. No. 5,813,142 by Demon, issuedSep. 29, 1998 and by the references cited therein.

FIGS. 11M-11P also include the inventor's concavely rounded sides asdescribed elsewhere in this application, such as FIGS. 11A-11L (and/orconcavely rounded underneath portions). In addition, FIGS. 11M-11P showducts that communicate between encapsulated midsole sections or bladders188 or within portions of the encapsulated midsole section chambers orbladders 188. Other suitable conventional embodiments can also be usedin combination with the applicant's concavely rounded portions. Also,FIGS. 11N-11P show insertable midsole orthotics 145. FIG. 11M shows anon-removable midsole 148 in combination with the pressure controlledbladder or encapsulated section 188 of the invention. The bladders orsections 188 can be any size relative to the midsole encapsulating them,including replacing the encapsulating midsole substantially or entirely.

Also, included in the applicant's invention, but not shown, is the useof a piezo-electric effect controlled by the microprocessor controlsystem to affect the hardness or firmness of the material contained inthe encapsulated midsole section, bladder, or other encapsulated midsolesection 188. For example, a disk-shaped midsole or other suitablematerial section 161 may be controlled by electric current flow insteadof fluid flow with common electrical components replacing thosedescribed below which are used for conducting and controlling fluid flowunder pressure.

FIG. 11M shows a shoe sole with the applicant's concavely rounded sides,invention described in earlier figures including both concavely roundedsole inner and outer surfaces, with a bladder or an encapsulated midsolesection 188 in both the medial and lateral sides and in the middle orunderneath portion between the sides. An embodiment with a bladder orencapsulated midsole section 188 located in only a single side and themiddle portion is also possible, but not shown, as is an embodiment witha bladder or encapsulated midsole section 188 located in both the medialand lateral sides without one in the middle portion. Each of thesections or bladders 188 is connected to an adjacent bladder(s)188 by afluid duct 206 passing through a fluid valve 210, located in midsole148, although the location could be anywhere in a single or multi-layerrounded shoe sole 28. FIG. 11M is based on the left side of FIG. 13A. Ina piezo-electric embodiment using bladders or encapsulated midsolesections 188, the fluid duct between sections would be replaced by asuitable wired or wireless connection, not shown. A combination of oneor more bladders 188 with one or more encapsulate midsole sections 188is also possible but not shown.

One advantage of the applicant's invention, as shown in the applicant'sFIG. 11M, is to provide better lateral or side-to-side stability throughthe use of rounded sides, to compensate for excessive pronation orsupination or both when standing or during locomotion. The FIG. 11Membodiment also shows a fluid containment system that is fully enclosedand which uses other bladders 188 as reservoirs to provide uniqueadvantage. The advantage of FIG. 11M embodiment is to provide astructural means by which to change the hardness or firmness of each ofthe shoe sole sides and of the middle or underneath sole portionrelative to the hardness or firmness of each of the other sides or soleportion, as seen for example in a frontal plane, as shown, or in asagittal plane (not shown).

Although FIG. 11M shows communication between each bladder or sectionwithin a frontal plane (or sagittal plane), which is a highly effectiveembodiment, communication might also be between only two adjacent ornon-adjacent bladders or encapsulated midsole sections 188 due to cost,weight, or other design considerations. The operation of the applicant'sinvention, beyond that described herein with the exceptions specificallyindicated, is as is known in the prior art, specifically the Demon '142patent, the relevant portions of which, such as the disclosure of asuitable system and electronic shown in schematic representations inFIGS. 2, 6 and 7 of the Demon '142 patent and the pressure sensitivevariable capacitor shown in FIG. 5, as well as the textual specificationassociated with those figures, are hereby incorporated by reference.

Each fluid bladder or encapsulated midsole section 188 may be providedwith an associated pressure sensing device that measures the pressureexerted by the user's foot on the fluid bladder or encapsulated midsolesection 188. As the pressure increases above a threshold, a controlsystem opens (perhaps only partially) a flow regulator to allow fluid toescape from the fluid bladder 188. Thus, the release of fluid from thefluid bladders 188 may be employed to reduce the impact of the user'sfoot on the ground. Point pressure under a single bladder 188, forexample, can be reduced by a controlled fluid outflow to any othersingle bladder or any combination of other bladders.

Preferably, the sole of the shoe is divided into zones which roughlycorrespond to the essential structural support and propulsion elementsof the intended wearer's foot, including the base of the calcaneus, thelateral tuberosity of the calcaneus 95, the heads of the metatarsals 96(particularly the first and fifth), the base of the fifth metatarsal,the main longitudinal arch (optional), and the head of the first distalphalange 98. The zones under each individual element can be merged withadjacent zones, such as a lateral metatarsal head zone 96 e and a medialmetatarsal head zone 96 d.

The pressure sensing system preferably measures the relative change inpressure in each of the zones. The fluid pressure system thereby reducesthe impact experienced by the user's foot by regulating the escape of afluid from a fluid bladder or encapsulated midsole section 188 locatedin each zone of the sole. The control system 300 receives pressure datafrom the pressure sensing system and controls the fluid pressure systemin accordance with predetermined criteria which can be implemented viaelectronic circuitry, software or other conventional means.

The pressure sensing system may include a pressure sensing device 104disposed in the sole of the shoe at each zone. In a preferredembodiment, the pressure sensing device 104 is a pressure sensitivevariable capacitor which may be formed by a pair of parallel flexibleconductive plates disposed on each side of a compressible dielectric.The dielectric, which can be made from any suitable material such asrubber or another suitable elastomer. The outside of flexible conductiveplates are preferably covered by a flexible sheath (such as rubber) foradded protection.

Since the capacitance of a parallel plate capacitor is inverselyproportional to the distance between the plates, compressing thedielectric by applying greater pressure increases the capacitance ofpressure sensitive variable capacitor. When the pressure is released,the dielectric expands substantially to its original thickness so thatthe pressure sensitive variable capacitor returns substantially to itsoriginal capacitance. Consequently, the dielectric must have arelatively high compression limit and a high degree of elasticity toprovide ideal function under variable loading.

The pressure sensing system also includes pressure sensing circuitry 120which converts the change in pressure detected by the variable capacitorinto digital data. Each variable capacitor forms part of a conventionalfrequency-to-voltage converter (FVC) which outputs a voltageproportional to the capacitance of variable capacitor. An adjustablereference oscillator may be electrically connected to each FVC. Thevoltage produced by each of the FVC's is provided as an input to amultiplexer which cycles through the channels sequentially connectingthe voltage from each FVC to an analog-to-digital (A/D) converter toconvert the analog voltages into digital data for transmission tocontrol system 300 via data lines, each of which is connected to controlsystem 300. The control system 300 can control the multiplexer toselectively receive data from each pressure sensing device in anydesirable order. These components and circuitry are well known to thoseskilled and the art and any suitable component or circuitry might beused to perform the same function.

The fluid pressure system selectively reduces the impact of the user'sfoot in each of the zones. Associated with each pressure sensing device104 in each zone, and embedded in the shoe sole, is at least one bladderor encapsulated midsole section 188 which forms part of the fluidpressure system. A fluid duct 206 is connected at its first end to itsrespective bladder or encapsulated midsole section 188 and is connectedat its other end to a fluid reservoir. In this embodiment, fluid duct206 connects bladder or encapsulated midsole section 188 with ambientair, which acts as a fluid reservoir, or in a different embodiment, withanother bladder 188 also acting as a fluid reservoir. A flow regulator,which in this embodiment is a fluid valve 210, is disposed in fluid duct206 to regulate the flow of fluid through fluid duct 206. Fluid valve210 is adjustable over a range of openings (i.e., variable metering) tocontrol the flow of fluid exiting bladder or section 188 and may be anysuitable conventional valve such as a solenoid valve as in thisembodiment.

Control system 300, which preferably includes a programmablemicrocomputer having conventional RAM and/or ROM, receives informationfrom the pressure sensing system indicative of the relative pressuresensed by each pressure sensing device 104. Control system 300 receivesdigital data from pressure sensing circuitry 120 proportional to therelative pressure sensed by pressure sensing devices 104. Control system300 is also in communication with fluid valves 210 to vary the openingof fluid valves 210 and thus control the flow of fluid. As the fluidvalves of this embodiment are solenoids (and thus electricallycontrolled), control system 300 is in electrical communication withfluid valves 210. An analog electronic control system 300 with othercomponents being analog is also possible.

The preferred programmable microcomputer of control system 300 selects(via a control line) one of the digital-to-analog (D/A) converters toreceive data from the microcomputer to control fluid valves 210. Theselected D/A converter receives the data and produces an analog voltageproportional to the digital data received. The output of each D/Aconverter remains constant until changed by the microcomputer (which canbe accomplished using conventional data latches, which is not shown).The output of each D/A converter is supplied to each of the respectivefluid valves 210 to selectively control the size of the opening of fluidvalves 210.

Control system 300 also can include a cushion adjustment control toallow the user to control the level of cushioning response from theshoe. A control device on the shoe can be adjusted by the user toprovide adjustments in cushioning ranging from no additional cushioning(fluid valves 210 never open) to maximum cushioning (fluid valves 210open wide). This is accomplished by scaling the data to be transmittedto the D/A converters (which controls the opening of fluid valves 210)by the amount of desired cushioning as received by control system 300from the cushioning adjustment control. However, any suitableconventional means of adjusting the cushioning could be used.

An illuminator, such as a conventional light emitting diode (LED), canbe mounted to the circuit board that houses the electronics of controlsystem 300 to provide the user with an indication of the state ofoperation of the apparatus.

The operation of this embodiment of the present invention is most usefulfor applications in which the user is either walking or running for anextended period of time during which weight is distributed among thezones of the foot in a cyclical pattern. The system begins by performingan initialization process which is used to set up pressure thresholdsfor each zone.

During initialization, fluid valves 210 are fully closed while thebladders or sections 188 are in their uncompressed state (e.g., beforethe user puts on the shoes). In this configuration, no fluid, includinga gas like air, can escape the bladders or encapsulated midsole sections188 regardless of the amount of pressure applied to the bladders orsections 188 by the user's foot. As the user begins to walk or run withthe shoes on, control system 300 receives and stores measurements of thechange in pressure of each zone from the pressure sensing system. Duringthis period, fluid valves 210 are kept closed.

Next, control system 300 computes a threshold pressure for each zonebased on the measured pressures for a given number of strides. In thisembodiment, the system counts a predetermined number of strides, i.e.ten strides (by counting the number of pressure changes), but anothersystem might simply store data for a given period of time (e.g. twentyseconds). The number of strides are preprogrammed into the microcomputerbut might be inputted by the user in other embodiments. Control system300 then examines the stored pressure data and calculates a thresholdpressure for each zone. The calculated threshold pressure, in thisembodiment, will be less than the average peak pressure measured and isin part determined by the ability of the associated bladder or section188 to reduce the force of the impact as explained in more detail below.

After initialization, control system 300 will continue to monitor datafrom the pressure sensing system and compare the pressure data from eachzone with the pressure threshold of that zone. When control system 300detects a measured pressure that is greater than the pressure thresholdfor that zone, control system 300 opens the fluid valve 210 (in a manneras discussed above) associated with that pressure zone to allow fluid toescape from the bladder or section 188 into the fluid reservoir at acontrolled rate. In this embodiment, air escapes from bladder or section188 through fluid duct 206 (and fluid valve 210 disposed therein) intoambient air. The release of fluid from the bladder or section 188 allowsthe bladder or section 188 to deform and thereby lessens the “push back”of the bladder. The user experiences a “softening” or enhancedcushioning of the sole of the shoe in that zone, which reduces theimpact on the user's foot in that zone.

The size of the opening of fluid valve 210 should allow fluid to escapethe bladder or section 188 in a controlled manner. The fluid should notescape from bladder or section 188 so quickly that the bladder orsection 188 becomes fully deflated (and can therefore supply noadditional cushioning) before the peak of the pressure exerted by theuser. However, the fluid must be allowed to escape from the bladder orsection 188 at a high enough rate to provide the desired cushioning.Factors which will bear on the size of the opening of the flow regulatorinclude the viscosity of the fluid, the size of the fluid bladder, thepressure exerted by fluid in the fluid reservoir, the peak pressureexerted and the length of time such pressure is maintained.

As the user's foot leaves the traveling surface, a fluid like air isforced back into the bladder or section 188 by a reduction in theinternal air pressure of the bladder or section 188 (i.e., a vacuum iscreated) as the bladder or section 188 returns to its non-compressedsize and shape. After control system 300 receives pressure data from thepressure sensing system indicating that no pressure (or minimalpressure) is being applied to the zones over a predetermined length oftime (long enough to indicate that the shoe is not in contact with thetraveling surface and that the bladders or sections 188 have returned totheir non-compressed size and shape), control system 300 again closesall fluid valves 210 in preparation for the next impact of the user'sfoot with the traveling surface.

Pressure sensing circuitry 120 and control system 300 are mounted to theshoe and are powered by a common, conventional battery supply. Aspressure sensing device 104 and the fluid system are generally locatedin the sole of the shoe, the described electrical connections arepreferably embedded in the upper and the sole of the shoe.

The FIG. 11M embodiment can also be modified to omit the applicant'sconcavely rounded sides and can be combined with the various features ofany one or more of the other figures included in this application, ascan the features of FIGS. 11N-11P. Pressure sensing devices 104 are alsoshown in FIG. 11M. A control system 300, such as a microprocessor asdescribed above, forms part of the embodiment shown in FIG. 11M (andFIGS. 11N-11O) embodiments, but is not shown in the frontal plane crosssection.

FIG. 11N shows the application of the FIG. 11M concept as describedabove in combination with an insertable midsole orthotic 145 invention.One significant advantage of this embodiment, besides improved lateralstability, is that the potentially most expensive component of the shoesole, the insertable midsole orthotic 145, can be moved to other pairsof shoe upper/bottom shoes, whether new or having a different style orfunction. Separate removable insoles can be useful in this case,especially in changing from athletic shoes to dress shoes for functionand/or style. FIG. 11N shows a simplified embodiment of only twobladders 188 or encapsulated midsole sections 188, each of which extendsfrom a concavely rounded side to the central portion. FIG. 11N is basedon the right side of FIG. 13A.

The FIG. 11O embodiment is similar to the FIG. 11N embodiment, exceptthat only one bladder or encapsulated midsole section 188 is shown,separated centrally by a wall 189 containing a fluid valve communicatingbetween the two separate parts of the section or bladder 188. The angleof the separating wall 189 provides a gradual transition from thepressure of the left compartment to the pressure of the rightcompartment, but is not required. Other structures may be present withinor outside the section or bladder 188 for support or other purposes, asis known in the art.

FIG. 11P is a perspective view of the applicant's invention, includingthe control system 300, such as a microprocessor, and pressure-sensingcircuitry 120, which can be located anywhere in the insertable midsoleorthotic 145 shown, in order for the entire unit to be removable as asingle piece, with placement in the shank shown proximate the mainlongitudinal arch of the wearer's foot shown in this figure, oralternatively, located elsewhere in the shoe, potentially with a wiredor wireless connection and potentially separate means of attachment. Theheel bladder 188 shown in FIG. 11P is similar to that shown in FIG. 11Owith both lateral and medial chambers.

Like FIG. 11M, FIGS. 11N-11P operate in the manner known in the art asdescribed above, except as otherwise shown or described herein by theapplicant, with the applicant's depicted embodiments being preferred butnot required.

The embodiments shown in FIGS. 11M-11P can also include the capabilityto function sufficiently rapidly to sense an unstable shoe solecondition such as, for example, that initiating a slip, trip, or fall,and to react to the unstable shoe condition in order to promote a stableor more stable shoe sole condition. In this manner, the system canattempt to prevent a fall or at least attempt to reduce associatedinjuries, for example, by rapidly reducing high point pressure in onezone of the shoe sole so that pressures in all zones are quicklyequalized to restore the stability of the shoe sole.

The insertable midsole orthotic 145 invention, for example as shown inFIGS. 11A-11P, can also be used in combination with, or to implement,one or more features of any of the applicant's prior inventions shown inthe other figures in this application. Such use can also include acombination of features shown in any other figures of the presentapplication. For example, the insertable midsole orthotic 145 of thepresent invention may replace all or any portion or portions of thevarious midsoles, insoles and bottom soles which are shown in thefigures of the present application, and may be combined with the variousother features described in reference to any of these figures in any ofthese forms.

The insertable midsole orthotic 145 shown in FIGS. 11A-11P can beintegrated into, or may replace an orthotic or other podiatric,orthopedic, corrective, therapeutic, prosthetic, prescriptive, orsimilar device for use inside the wearer's shoe. Such devices can berigid, but flexible devices are preferred. A more conventional devicesuch as an orthotic without concavely rounded sides or lower surface canbe placed on top of the midsole, or between the midsole and an insole,on top of the midsole, or in any other suitable location. Other portionsof the shoe sole 28 may include the concavely rounded side or sides orunderneath portions.

If the insertable midsole orthotic 145 is used to replace an orthotic,for example, then any of the features of an orthotic can be provided byan equivalent feature, structural support, cushioning or otherwise, inthe insertable midsole orthotic 145. If a midsole is integrated with aninsertable midsole orthotic 145, for example, then the midsole might bea mass-produced lower layer providing cushioning and support, as well asheel lift, while the insertable midsole orthotic 145 might be rounded tothe exact shape of the individual wearer's foot and could provide otherstructural or functional corrections specific to the individual wearer.Alternatively, part of the correction might be made in the midsole, suchas, for example, the provision of a medial side increase in materialfirmness to compensate for an individual wearer's excessive pronation.

As shown in FIGS. 11Q and 11R, the insertable midsole orthotic 145 caninclude its own integral inner or secondary upper 21 a, such as a bootieor slipper incorporating stretchable fabric, i.e. elastic or Spandex®,non-stretchable fabric or both, with typical attachment means such aslaces, straps, Velcro® and zippers, or simply be a slip-on structure,like a slipper or loafer or pull-on boot.

FIGS. 11Q and 11R also show the insertable midsole orthotic 145 with itsown thin outer sole 149 a such as of rubber or other suitable, typicalmaterial for wear protection of the midsole and for traction, so thatthe insertable midsole orthotic 145 can be worn indoors, for example,without the shoe upper 21 and outer sole 149, but can also be insertedinto, for example, the FIG. 11C upper and sole for heavier use, such aswalking outdoors or engaging in athletics. Separate components or anentire outer sole 149 can also be affixed directly to the insertablemidsole orthotic 145 with a sufficiently durable secondary upper 21 ausing conventional means for affixing it, such as the interface surface8 of the outer soles 149 and 149 a interlocking geometrically, as shownin FIGS. 11E and 11F, in conjunction with straps, or with straps alone,roughly in the manner of sandals. Similarly, all or part of the shoeupper 21 can be affixed through conventional means to the secondary shoeupper 21 a, independently of the outer sole 149 or in combination withit.

FIGS. 11Q-11S show an embodiment of an orthotic inner shoe in accordancewith the present invention. FIG. 11Q shows, in frontal plane crosssection, an embodiment with a very thin coat of traction material suchas latex rubber forming a secondary outer sole 149 a which providestraction to prevent slipping and also protects the insertable midsoleorthotic 145 underneath from wear, and a lowtop slipper inner upper 21a. Such a latex rubber coat can be applied in a continuous manner overpart or all of the outer surface of the secondary outer sole 149 a orcan be applied in a regular pattern, like dots or circles, as is typicalto provide better grip for gloves, or can even be applied in a randompattern.

FIG. 11R shows, in frontal plane cross section, another embodiment witha secondary bottom or outer sole 149 a of a rubber material that mightbe as thin as 1 millimeter, for example, to protect just that part ofthe insertable midsole orthotic 145 which makes contact with the ground43 when the intended wearer's foot is upright and therefore that midsolepart which would wear most quickly due to a high level of groundcontact. Other suitable outsole material can be used. Although notshown, the secondary outer sole 149 a can extend part or all the way upeither or both of the rounded shoe sole lateral and medial sides.

FIG. 11R also shows a lowtop slipper inner secondary upper 21 a whichcan envelop all or a portion of the midsole sides, including joiningwith the secondary outer sole 149 a, such as overlapping it on theinside between the insertable midsole orthotic 145 and the outer sole149 a. FIG. 11Q shows the secondary upper 21 a connecting to the insole2. The secondary upper 21 a can also envelop the insole, although notshown.

FIG. 11S shows in close-up cross section the interface surface 8 betweenthe bottom sole 149 and the secondary bottom sole 149 a of theinsertable midsole orthotic 145. Direct contact, as shown of the rubberor rubber-like materials or 149 and 149 a, provides an excellent meansinside the shoe sole to prevent internal slipping due to shear forces atthe interface surface 8, thereby increasing the stability of the shoesole. Therefore, removal of typical materials other than those of 149and 149 a, such as board last material, increases stability. This can beaccomplished by outright removal of a board last after the upper towhich it is attached has been assembled on a last or assembling withouta lasting board. Alternatively, by using a board last with holes orsections removed so that direct contact can occur at 149 and 149 a; suchholes or sections can be random or regular, including simply a veryloose weave fabric, or can coincide with some or all of the essentialsupport and propulsion elements of the foot described earlier, such asthe pattern shown in FIG. 70.

In an advantageous embodiment, most or all of the corrective portion ofthe insertable midsole orthotic 145, such as special shaping orincreased density inserts to compensate for an individual wearer'sstructural defects, is located in the upper portion of the insertablemidsole orthotic 145 where it is accessible through the opening of thesecondary upper 21 a for alteration so that it can be modified to bettercompensate for defects based on testing and usage of the intendedwearer.

In another advantageous embodiment, only this uppermost correctiveportion is the insertable midsole orthotic 145, while the lower portionof the midsole is fixed in a conventional manner in the shoe sole. Suchan embodiment can still be constructed using the embodiments describedabove, including FIGS. 11A-11S, especially including FIGS. 11Q-11R, andthe compartments with computer control mechanisms, particularly as shownin FIG. 11P. The uppermost insertable midsole orthotic 145 might includethe relatively expensive computer microprocessor and associated memory,for example, which might communicate with the remaining portions of thecompartment pressure controlling system using a wireless communicationsystem.

In one advantageous embodiment, the thickness of the uppermost portionof the insertable midsole orthotic 145 as described in FIGS. 11A-11S canbe any thickness less than half of the thickness of the shoe sole,including, but not limited to, in a comparison of median thicknesses. Inother embodiments, the thickness may be substantially less than half,for example, 40% of the total thickness, 30% of the total thickness oreven up to 20% of the total thickness.

FIGS. 12A-C show a series of conventional shoe sole cross sections inthe frontal plane at the heel utilizing both sagittal plane 181 andhorizontal plane sipes 182, and in which some or all of the sipes do notoriginate from any outer shoe sole surface, but rather are entirelyinternal. Relative motion between internal surfaces is thereby madepossible to facilitate the natural deformation of the shoe sole.

FIG. 12A shows a group of three midsole section or lamination layers.Preferably, the central layer 188 is not glued to the other surfaces incontact with it. Instead, those surfaces are internal deformation sipesin the sagittal plane 181 and in the horizontal plane 182, whichencapsulate the central layer 188, either completely or partially. Therelative motion between midsole section layers at the deformation sipes181 and 182 can be enhanced with lubricating agents, either wet likesilicone or dry like Teflon, of any degree of viscosity. Shoe solematerials can be closed cell if necessary to contain the lubricatingagent or a non-porous surface coating or layer of lubricant can beapplied. The deformation sipes can be enlarged to channels or any otherpractical geometric shape as sipes defined in the broadest possibleterms.

The relative motion can be diminished by the use of roughened surfacesor other conventional methods of increasing the coefficient of frictionbetween midsole section layers. If even greater control of the relativemotion of the central layer 188 is desired, as few as one or many morepoints can be glued together anywhere on the internal deformation sipes181 and 182, making them discontinuous, and the glue can be any degreeof elastic or inelastic.

In FIG. 12A, the outside structure of the sagittal plane deformationsipes 181 is the shoe upper 21, which is typically flexible andrelatively elastic fabric or leather. In the absence of any connectiveouter material like the shoe upper shown in FIG. 12A, just the outeredges of the horizontal plane deformation sipes 182 can be gluedtogether.

FIG. 12B shows another conventional shoe sole in frontal plane crosssection at the heel with a combination similar to FIG. 12A of bothhorizontal and sagittal plane deformation sipes that encapsulate acentral section 188. Like FIG. 12A, the FIG. 12B structure allows therelative motion of the central section 188 with its encapsulating outermidsole section 184, which encompasses its sides as well as the topsurface, and bottom sole 149, both of which are attached at their commonboundaries 8.

This FIG. 12B approach is analogous to the applicant's fully roundedshoe sole invention with an encapsulated midsole chamber of apressure-transmitting medium like silicone; in this conventional shoesole case, however, the pressure-transmitting medium is a moreconventional section of a typical shoe cushioning material like PV orEVA, which also provides cushioning.

FIG. 12C is another conventional shoe sole shown in frontal plane crosssection at the heel with a combination similar to FIGS. 12A and 12B ofboth horizontal and sagittal plane deformation sipes. However, insteadof encapsulating a central section 188, in FIG. 12C an upper section 187is partially encapsulated by deformation sipes so that it acts much likethe central section 188, but is more stable and more closely analogousto the actual structure of the human foot.

The upper section 187 would be analogous to the integrated mass of fattypads, which are U-shaped and attached to the calcaneus or heel bone.Similarly, the shape of the deformation sipes is U-shaped in FIG. 12Cand the upper section 187 is attached to the heel by the shoe upper, soit should function in a similar fashion to the aggregate action of thefatty pads. The major benefit of the FIG. 12C invention is that theapproach is so much simpler and therefore easier and faster to implementthan the highly complicated anthropomorphic design shown in FIG. 10above. The midsole sides 185 shown in FIG. 12C are like the side portionof the encapsulating midsole 184 in FIG. 12B.

FIG. 12D shows in a frontal plane cross section at the heel a similarapproach applied to the applicant's fully rounded design. FIG. 12D showsa design including an encapsulating chamber and a variation of theattachment for attaching the shoe upper to the bottom sole.

The left side of FIG. 12D shows a variation of the encapsulation of acentral section 188 shown in FIG. 12B, but the encapsulation is onlypartial, with a center upper section of the central section 188 eitherattached or continuous with the encapsulating outer midsole section 184.

The right side of FIG. 12D shows a structure of deformation sipes likethat of FIG. 12C, with the upper midsole section 187 provided with thecapability of moving relative to both the bottom sole and the side ofthe midsole. The FIG. 12D structure varies from that of FIG. 12C also inthat the deformation sipe 181 in roughly the sagittal plane is partialonly and does not extend to the upper surface 30 of the midsole 147, asit does FIG. 12C.

FIGS. 13A & 13B show, in frontal plane cross section at the heel area,shoe sole structures like FIGS. 5A & B, but in more detail and with thebottom sole 149 extending relatively farther up the side of the midsole.

The right side of FIGS. 13A & 13B show the preferred embodiment, whichis a relatively thin and tapering portion of the bottom sole extendingup most of the midsole and is attached to the midsole and to the shoeupper 21, which is also attached preferably first to the upper midsole147 where both meet at 3 and then attached to the bottom sole where bothmeet at 4. The bottom sole is also attached to the upper midsole 147where they join at 5 and to the midsole 148 at 6.

The left side of FIGS. 13A & 13B show a more conventional attachmentarrangement, where the shoe sole is attached to a fully lasted shoeupper 21. The bottom sole 149 is attached to: the midsole 148 wheretheir surfaces coincide at 6, the upper midsole 147 at 5, and the shoeupper 21 at 4.

FIG. 13A shows a shoe sole with another variation of an encapsulatedsection 188. The encapsulated section 188 is shown bounded by the bottomsole 149 at line 8 and by the rest of the midsole 147 and 148 at line 9.FIG. 13A shows more detail than prior figures, including an insole (alsocalled sock liner) 2, which is rounded to the shape of the wearer's footsole, just like the rest of the shoe sole, so that the foot sole issupported throughout its entire range of sideways motion, from maximumsupination to maximum pronation.

The insole 2 overlaps the shoe upper 21 at 13. This approach ensuresthat the load-bearing surface of the wearer's foot sole does not come incontact with any seams which could cause abrasions. Although only theheel section is shown in this figure, the same insole structure wouldpreferably be used elsewhere, particularly the forefoot. Preferably, theinsole would coincide with the entire load-bearing surface of thewearer's foot sole, including the front surface of the toes, to providesupport for front-to-back motion as well as sideways motion.

The FIG. 13 design provides firm flexibility by encapsulating fully orpartially, roughly the middle section of the relatively thick heel ofthe shoe sole (or of other areas of the sole, such as any or all of theessential support elements of the foot, including the base of the fifthmetatarsal, the heads of the metatarsals, and the first distalphalange). The outer surfaces of that encapsulated section or sectionsare allowed to move relatively freely by not gluing the encapsulatedsection to the surrounding shoe sole.

Firmness in the FIG. 13 design is provided by the high pressure createdunder multiples of body weight loads during locomotion within theencapsulated section or sections, making it relatively hard underextreme pressure, roughly like the heel of the foot. Unlike conventionalshoe soles, which are relatively inflexible and thereby create localpoint pressures, particularly at the outside edge of the shoe sole, theFIG. 13 design tends to distribute pressure evenly throughout theencapsulated section, so the natural biomechanics of the wearer's footsole are maintained and shearing forces are more effectively dealt with.

In the FIG. 13A design, firm flexibility is provided by encapsulatingroughly the middle section of the relatively thick heel of the shoe soleor other areas of the sole, while allowing the outer surfaces of thatsection to move relatively freely by not conventionally gluing theencapsulated section to the surrounding shoe sole. Firmness is providedby the high pressure created under body weight loads within theencapsulated section, making it relatively hard under extreme pressure,roughly like the heel of the foot, because it is surrounded by flexiblebut relatively inelastic materials, particularly the bottom sole 149(and connecting to the shoe sole upper, which also can be constructed byflexible and relatively inelastic material. The same U-shaped structureis thus formed on a macro level by the shoe sole that is constructed ona micro level in the human foot sole, as described definitively by ErichBlechschmidt in Foot and Ankle, March, 1982.

In summary, the FIG. 13A design shows a shoe construction for a shoe,comprising: a shoe sole with at least one compartment under thestructural elements of the human foot; the compartment containing apressure-transmitting medium composed of an independent section ofmidsole material that is not firmly attached to the shoe solesurrounding it; pressure from normal load-bearing is transmittedprogressively at least in part to the relatively inelastic sides, topand bottom of said shoe sole compartment, producing tension.

The FIG. 13A design can be combined with the designs shown in FIGS.58-60 so that the compartment is surrounded by a reinforcing layer ofrelatively flexible and inelastic fiber.

FIGS. 13A & 13B shows constant shoe sole thickness in frontal planecross-sections, but that thickness can vary somewhat (up to roughly 25%in some cases) in frontal plane cross-sections. FIG. 13B shows a designjust like FIG. 13A, except that the encapsulated section is reduced toonly the load-bearing boundary layer between the midsole 148 and thebottom sole 149. In simple terms, then, most or all of the upper surfaceof the bottom sole and the lower surface of the midsole are notattached, or at least not firmly attached, where they coincide at line8. The bottom sole and midsole are firmly attached only along thenon-load-bearing sides of the midsole. This approach is simple and easy.The load-bearing boundary layer 8 is like the internal horizontal sipedescribed in FIG. 12 above. The sipe can be a channel filled withflexible material or it can simply be a thinner chamber.

The boundary area 8 can be unglued, so that relative motion between thetwo surfaces is controlled only by their structural attachment togetherat the sides. In addition, the boundary area can be lubricated tofacilitate relative motion between surfaces or lubricated by a viscousliquid that restricts motion. Or the boundary area 8 can be glued with asemi-elastic or semi-adhesive glue that controls relative motion butstill permits some motion. The semi-elastic or semi-adhesive glue wouldthen serve a shock absorption function as well.

In summary, the FIG. 13B design shows a shoe construction for a shoe,comprising: a shoe upper and a shoe sole that has a bottom portion withsides that are relatively flexible and inelastic; at least a portion ofthe bottom sole sides firmly attach directly to the shoe upper; a shoeupper that is composed of material that is flexible and relativelyinelastic at least where the shoe upper is attached to the bottom sole;the attached portions enveloping the other sole portions of the shoesole; and the shoe sole having at least one horizontal boundary areaserving as a sipe that is contained internally within the shoe sole. TheFIG. 13B design can be combined with FIGS. 58-60 to include a shoe solebottom portion composed of material reinforced with at least one fiberlayer that is relatively flexible and inelastic and that is oriented inthe horizontal plane.

FIGS. 14, 15, and 16 show frontal plane cross sectional views of a shoesole according to the applicant's prior inventions based on theTheoretically Ideal Stability Plane, taken at about the ankle joint toshow the heel section of the shoe. FIGS. 17 through 26 show the sameview of the applicant's enhancement of that invention. In the figures, afoot 27 is positioned in a naturally rounded shoe having an upper 21 anda rounded shoe sole 28. The shoe sole normally contacts the ground 43 atabout the lower central heel portion thereof, as shown in FIG. 17. Theconcept of the Theoretically Ideal Stability Plane defines the plane 51in terms of a locus of points determined by the thickness(es) of thesole.

FIG. 14 shows, in a rear cross sectional view, the inner surface of theshoe sole conforming to the natural rounded of the foot and thethickness of the shoe sole remaining constant in the frontal plane, sothat the outer surface coincides with the Theoretically Ideal StabilityPlane.

FIG. 15 shows a fully rounded shoe sole design that follows the naturalrounded of all of the foot, the bottom as well as the sides, whileretaining a constant shoe sole thickness in the frontal plane.

The fully rounded shoe sole assumes that the resulting slightly roundedbottom when unloaded will deform under load and flatten just as thehuman foot bottom is slightly rounded unloaded but flattens under load.Therefore, the shoe sole material must be of such composition as toallow the natural deformation following that of the foot. The designapplies particularly to the heel, but to the rest of the shoe sole aswell. By providing the closest match to the natural shape of the foot,the fully rounded design allows the foot to function as naturally aspossible. Under load, FIG. 15 would deform by flattening to lookessentially like FIG. 14. Seen in this light, the naturally rounded sidedesign in FIG. 14 is a more conventional, conservative design that is aspecial case of the more general fully rounded design in FIG. 15, whichis the closest to the natural form of the foot, but the leastconventional. The amount of deformation flattening used in the FIG. 14design, which obviously varies under different loads, is not anessential element of the applicant's invention.

FIGS. 14 and 15 both show in frontal plane cross-sections theTheoretically Ideal Stability Plane, which is also theoretically idealfor efficient natural motion of all kinds, including running, jogging orwalking. FIG. 15 shows the most general case, the fully rounded design,which conforms to the natural shape of the unloaded foot. For any givenindividual, the Theoretically Ideal Stability Plane 51 is determined,first, by the desired shoe sole thickness(es) in a frontal plane crosssection, and, second, by the natural shape of the individual's footsurface 29.

For the special case shown in FIG. 14, the Theoretically Ideal StabilityPlane for any particular individual (or size average of individuals) isdetermined, first, by the given frontal plane cross section shoe solethickness(es); second, by the natural shape of the individual's foot;and, third, by the frontal plane cross-section width of the individualsload-bearing footprint 30 b, which is defined as the upper surface ofthe shoe sole that is in physical contact with and supports the humanfoot sole.

The Theoretically Ideal Stability Plane for the special case is composedconceptually of two parts. Shown in FIG. 14, the first part is a linesegment 31 b of equal length and parallel to line 30 b at a constantdistance(s) equal to shoe sole thickness. This corresponds to aconventional shoe sole directly underneath the human foot, and alsocorresponds to the flattened portion of the bottom of the load-bearingshoe sole 28 b. The second part is the naturally rounded stability sideouter edge 31 a located at each side of the first part, line segment 31b. Each point on the rounded side outer edge 31 a is located at adistance which is exactly the shoe sole thickness (s) from the closestpoint on the rounded side inner edge 30 a.

In summary, the Theoretically Ideal Stability Plane is used to determinea geometrically precise bottom contour of the shoe sole based on a topcontour that conforms to the contour of the foot.

It can be stated unequivocally that any shoe sole contour, even ofsimilar contour, that exceeds the Theoretically Ideal Stability Planewill restrict natural foot motion, while any less than that plane willdegrade natural stability, in direct proportion to the amount of thedeviation. The theoretical ideal was taken to be that which is closestto natural.

FIG. 16 illustrates in frontal plane cross-section another variation ofa shoe sole that uses stabilizing quadrants 26 at the outer edge of aconventional shoe sole 28 b illustrated generally at the referencenumeral 28. The stabilizing quadrants would be abbreviated in actualembodiments.

FIG. 17 illustrates the shoe sole side thickness increasing beyond theTheoretically Ideal Stability Plane to increase stability somewhatbeyond its natural level. The unavoidable trade-off which results isthat natural motion would be restricted somewhat and the weight of theshoe sole would increase somewhat.

FIG. 17 shows a situation wherein the thickness of the sole at each ofthe opposed sides is thicker at the portions of the sole 31 a by athickness which gradually varies continuously from a thickness (s)through a thickness (s+s1), to a thickness (s+s2). These designsrecognize that lifetime use of existing shoes, the design of which hasan inherent problem that continually disrupts natural humanbiomechanics, has produced thereby actual structural changes in a humanfoot and ankle to an extent that must be compensated for. Specifically,one of the most common of the abnormal effects of the inherent existingproblem is a weakening of the long arch of the foot, increasingpronation. These designs therefore provide greater than naturalstability and should be particularly useful to individuals, generallywith low arches, prone to pronate excessively, and could be used only onthe medial side. Similarly, individuals with high arches and a tendencyto over supinate and who are vulnerable to lateral ankle sprains wouldalso benefit, and the design could be used only on the lateral side. Ashoe for the general population that compensates for both weaknesses inthe same shoe would incorporate the enhanced stability of the designcompensation on both sides.

FIG. 17, like FIGS. 14 and 15, shows an embodiment which allows the shoesole to deform naturally, closely paralleling the natural deformation ofthe bare foot under load. In addition, shoe sole material must be ofsuch composition as to allow natural deformation similar to that of thefoot.

This design retains the concept of contouring the shape of the shoe soleto the shape of the human foot. The difference is that the shoe solethickness in the frontal plane is allowed to vary rather than remainuniformly constant. More specifically, FIGS. 17, 18, 19, 20, and 24show, in frontal plane cross sections at the heel, that the shoe solethickness can increase beyond the Theoretically Ideal Stability Plane51, in order to provide greater than natural stability. Such variations(and the following variations) can be consistent through all frontalplane cross sections, so that there are proportionately equal increasesto the Theoretically Ideal Stability Plane 51 from the front of the shoesole to the back. Alternatively, the thickness can vary, preferablycontinuously, from one frontal plane to the next.

The exact amount of the increase in shoe sole thickness beyond theTheoretically Ideal Stability Plane is to be determined empirically.Ideally, right and left shoe soles would be custom designed for eachindividual based on a biomechanical analysis of the extent of his or herfoot and ankle dysfunction in order to provide an optimal individualcorrection. If epidemiological studies indicate general correctivepatterns for specific categories of individuals or the population as awhole, then mass-produced corrective shoes with soles incorporatingrounded sides having a thickness exceeding the Theoretically IdealStability Plane would be possible. It is expected that any suchmass-produced corrective shoes for the general population would havethicknesses exceeding the Theoretically Ideal Stability Plane by anamount up to 5 or 10 percent, while more specific groups or individualswith more severe dysfunction could have an empirically demonstrated needfor greater corrective thicknesses on the order of up to 25 percent morethan the Theoretically Ideal Stability Plane. The optimal rounded forthe increased thickness may also be determined empirically.

FIG. 18 shows a variation of the enhanced fully rounded design whereinthe shoe sole begins to thicken beyond the Theoretically Ideal StabilityPlane 51 somewhat offset to the sides.

FIG. 19 shows a thickness variation which is symmetrical as in the caseof FIGS. 17 and 18, but wherein the shoe sole begins to thicken beyondthe Theoretically Ideal Stability Plane 51 directly underneath the footheel 27 on about a center line of the shoe sole. In fact, in this casethe thickness of the shoe sole is the same as the Theoretically IdealStability Plane only at that beginning point underneath the uprightfoot. For the embodiment wherein the shoe sole thickness varies, theTheoretically Ideal Stability Plane is determined by the least thicknessin the shoe sole's direct load-bearing portion meaning that portion withdirect tread contact on the ground. The outer edge or periphery of theshoe sole is obviously excluded, since the thickness there alwaysdecreases to zero. Note that the capability of the design to deformnaturally may make some portions of the shoe sole load-bearing when theyare actually under a load, especially walling or running, even thoughthey may not be when the shoe sole is not under a load.

FIG. 20 shows that the thickness can also increase and then decrease.Other thickness variation sequences are also possible. The variation inside rounded thickness can be either symmetrical on both sides orasymmetrical, particularly with the medial side providing more stabilitythan the lateral side, although many other asymmetrical variations arepossible. Also, the pattern of the right foot can vary from that of theleft foot.

FIGS. 21, 22, 23 and 25 show that similar variations in shoe midsole(other portions of the shoe sole area not shown) density can providesimilar, but reduced, effects to the variations in shoe sole thicknessdescribed previously in FIGS. 17-20. The major advantage of thisapproach is that the structural Theoretically Ideal Stability Plane isretained, so that naturally optimal stability and efficient motion areretained to the maximum extent possible.

The forms of dual and tri-density midsoles shown in the figures areextremely common in the current art of athletic shoes, and any number ofdensities are theoretically possible, although an angled alternation ofjust two densities like that shown in FIG. 21 provides continuallychanging composite density. However, multi-densities in the midsole werenot preferred since only a uniform density provides a neutral shoe soledesign that does not interfere with natural foot and ankle biomechanicsin the way that multi-density shoe soles do, which is by providingdifferent amounts of support to different parts of the foot. In thesefigures, the density of the sole material designated by the legend (d¹)is firmer than (d) while (d²) is the firmest of the three representativedensities shown. In FIG. 21, a dual density sole is shown, with (d)having the less firm density.

It should be noted that shoe soles using a combination both of solethicknesses greater than the Theoretically Ideal Stability Plane and ofmidsole density variations like those just described are also possiblebut not shown.

FIG. 26 shows a bottom sole tread design that provides about the sameoverall shoe sole density variation as that provided in FIG. 23 bymidsole density variation. The less supporting tread there is under anyparticular portion of the shoe sole, the less effective overall shoesole density there is, since the midsole above that portion will deformmore easily than if it were fully supported.

FIG. 27 shows embodiments like those in FIGS. 17 through 26 but whereina portion of the shoe sole thickness is decreased to less than theTheoretically Ideal Stability Plane. It is anticipated that someindividuals with foot and ankle biomechanics that have been degraded byexisting shoes may benefit from such embodiments, which would provideless than natural stability but greater freedom of motion, and less shoesole weight and bulk. In particular, it is anticipated that individualswith overly rigid feet, those with restricted range of motion, and thosetending to over-supinate may benefit from the FIG. 14 embodiments. Evenmore particularly, it is expected that the invention will benefitindividuals with significant bilateral foot function asymmetry: namely,a tendency toward pronation on one foot and supination on the otherfoot. Consequently, it is anticipated that this embodiment would be usedonly on the shoe sole of the supinating foot, and on the inside portiononly, possibly only a portion thereof. It is expected that the rangeless than the Theoretically Ideal Stability Plane would be a maximum ofabout five to ten percent, though a maximum of up to twenty-five percentmay be beneficial to some individuals.

FIG. 27A shows an embodiment like FIGS. 17 and 20, but with naturallyrounded sides less than the Theoretically Ideal Stability Plane. FIG.27B shows an embodiment like the fully rounded design in FIGS. 18 and19, but with a shoe sole thickness decreasing with increasing distancefrom the center portion of the sole. FIG. 27C shows an embodiment likethe quadrant-sided design of FIG. 24, but with the quadrant sidesincreasingly reduced from the Theoretically Ideal Stability Plane.

The lesser-sided design of FIG. 27 would also apply to the FIGS. 21-23and density variation approach and to the FIG. 26 approach using treaddesign to approximate density variation.

FIG. 28A-28C show, in cross-sections that with the quadrant-sided designof FIGS. 16, 24, 25 and 27C that it is possible to have shoe sole sidesthat are both greater and lesser than the Theoretically Ideal StabilityPlane in the same shoe. The radius of an intermediate shoe solethickness, taken at (s²) at the base of the fifth metatarsal in FIG.28B, is maintained constant throughout the quadrant sides of the shoesole, including both the heel, FIG. 28C, and the forefoot, FIG. 28A, sothat the side thickness is less than the Theoretically Ideal StabilityPlane at the heel and more at the forefoot. Though possible, this is nota preferred approach.

The same approach can be applied to the naturally rounded sides or fullyrounded designs described in FIGS. 14, 15, 17-23 and 26, but it is alsonot preferred. In addition, as shown in FIGS. 28D-28F, it is possible tohave shoe sole sides that are both greater and lesser than theTheoretically Ideal Stability Plane in the same shoe, like FIGS.28A-28C, but wherein the side thickness (or radius) is neither constantlike FIGS. 28A-28C or varying directly with shoe sole thickness, butinstead varying quite indirectly with shoe sole thickness. As shown inFIGS. 28D-28F, the shoe sole side thickness varies from somewhat lessthan the shoe sole thickness at the heel to somewhat more at theforefoot. This approach, though possible, is again not preferred, andcan be applied to the quadrant sided design, but is not preferred thereeither.

FIG. 29 shows in a frontal plane cross-section at the heel (center ofankle joint) the general concept of a shoe sole 28 that conforms to thenatural shape of the human foot 27 and that has a constant thickness (s)in frontal plane cross sections. The surface 29 of the bottom and sidesof the foot 27 should correspond exactly to the upper surface 30 of theshoe sole 28. The shoe sole thickness is defined as the shortestdistance (s) between any point on the upper surface 30 of the shoe sole28 and the lower surface 31. In effect, the applicant's general conceptis a shoe sole 28 that wraps around and conforms to the natural contoursof the foot 27 as if the shoe sole 28 were made of a theoretical singleflat sheet of shoe sole material of uniform thickness, wrapped aroundthe foot with no distortion or deformation of that sheet as it is bentto the foot's contours. To overcome real world deformation problemsassociated with such bending or wrapping around contours, actualconstruction of the shoe sole contours of uniform thickness willpreferably involve the use of multiple sheet lamination or injectionmolding techniques.

FIGS. 30A, 30B, and 30C illustrate in frontal plane cross-section use ofnaturally rounded stabilizing sides 28 a at the outer edge of a shoesole 28 b illustrated generally at the reference numeral 28. Thiseliminates the unnatural sharp bottom edge, especially of flared shoes,in favor of a naturally rounded shoe sole outside 31 as shown in FIG.29. The side or inner edge 30 a of the shoe sole stability side 28 a isrounded like the natural form on the side or edge of the human foot, asis the outside or outer edge 31 a of the shoe sole stability side 28 ato follow a Theoretically Ideal Stability Plane. The thickness (s) ofthe shoe sole 28 is maintained exactly constant, even if the shoe soleis tilted to either side, or forward or backward. Thus, the naturallyrounded stabilizing sides 28 a, are defined as the same as the thickness33 of the shoe sole 28 so that, in cross-section, the shoe solecomprises a stable shoe sole 28 having at its outer edge naturallyrounded stabilizing sides 28 a with a surface 31 a representing aportion of a Theoretically Ideal Stability Plane and described bynaturally rounded sides equal to the thickness (s) of the sole 28. Thetop of the shoe sole 30 b coincides with the shoe wearer's load-bearingfootprint, since in the case shown the shape of the foot is assumed tobe load-bearing and therefore flat along the bottom. A top edge 32 ofthe naturally rounded stability side 28 a can be located at any pointalong the rounded side of the outer surface of the foot 29, while theinner edge 33 of the naturally rounded side 28 a coincides with theperpendicular sides 34 of the load-bearing shoe sole 28 b. In practice,the shoe sole 28 is preferably integrally formed from the portions 28 band 28 a. Thus, the Theoretically Ideal Stability Plane includes thecontours 31 a merging into the lower surface 31 b of the rounded shoesole 28.

Preferably, the peripheral extent 36 of the load-bearing portion of thesole 28 b of the shoe includes all of the support structures of the footbut extends no further than the outer edge of the foot sole 37 asdefined by a load-bearing footprint, as shown in FIG. 30D, which is atop view of the upper shoe sole surface 30 b . FIG. 30D thus illustratesa foot outline at numeral 37 and a recommended sole outline 36 relativethereto. Thus, a horizontal plane outline of the top of the load-bearingportion of the shoe sole, therefore exclusive of rounded stabilitysides, should, preferably, coincide as nearly as practicable with theload-bearing portion of the foot sole with which it comes into contact.Such a horizontal outline, as best seen in FIGS. 30D and 33D, shouldremain uniform throughout the entire thickness of the shoe soleeliminating negative or positive sole flare so that the sides areexactly perpendicular to the horizontal plane as shown in FIG. 30B.Preferably, the density of the shoe sole material is uniform.

As shown diagrammatically in FIG. 31, preferably, as the heel lift orwedge 38 of thickness (s1) increases the total thickness (s+s1) of thecombined midsole and outer sole 39 of thickness (s) in an aft directionof the shoe, the naturally rounded sides 28 a increase in thicknessexactly the same amount according to the principles discussed inconnection with FIG. 30. Thus, the thickness of the inner edge 33 of thenaturally rounded side is always equal to the constant thickness (s) ofthe load-bearing shoe sole 28 b in the frontal cross-sectional plane.

As shown in FIG. 31B, for a shoe that follows a more conventionalhorizontal plane outline, the sole can be improved significantly by theaddition of a naturally rounded side 28 a which correspondingly varieswith the thickness of the shoe sole and changes in the frontal planeaccording to the shoe heel lift 38. Thus, as illustrated in FIG. 31B,the thickness of the naturally rounded side 28 a in the heel section isequal to the thickness (s+s1) of the shoe sole 28 which is thicker thanthe shoe sole 39 thickness (s) shown in FIG. 31A by an amount equivalentto the heel lift 38 thickness (s1). In the generalized case, thethickness (s) of the rounded side is thus always equal to the thickness(s) of the shoe sole.

FIG. 32 illustrates a side cross-sectional view of a shoe to which theinvention has been applied and is also shown in a top plane view in FIG.33.

Thus, FIGS. 33A, 33B, and 33C represent frontal plane cross-sectionstaken along the forefoot, at the base of the fifth metatarsal, and atthe heel, thus illustrating that the shoe sole thickness is constant ateach frontal plane cross-section, even though that thickness varies fromfront to back, due to the heel lift 38 as shown in FIG. 32, and that thethickness of the naturally rounded sides is equal to the shoe solethickness in each FIG. 33A-33C cross section. Moreover, in FIG. 33D, ahorizontal plane overview of the left foot, it can be seen that therounded of the sole follows the preferred principle in matching, asnearly as practical, the load-bearing sole print shown in FIG. 30D.

FIG. 34 illustrates an embodiment of the invention which utilizesvarying portions of the Theoretically Ideal Stability Plane 51 in thenaturally rounded sides 28 a in order to reduce the weight and bulk ofthe sole, while accepting a sacrifice in some stability of the shoe.Thus, FIG. 34A illustrates the preferred embodiment as described abovein connection with FIG. 31 wherein the outer edge 31 a of the naturallyrounded sides 28 a follows a Theoretically Ideal Stability Plane 51. Asin FIGS. 29 and 30, the rounded surfaces 31 a, and the lower surface ofthe sole 31 b lie along the Theoretically Ideal Stability Plane 51. Asshown in FIG. 34B, an engineering trade-off results in an abbreviationwithin the Theoretically Ideal Stability Plane 51 by forming a naturallyrounded side surface 53 a approximating the natural rounded of the foot(or more geometrically regular, which is less preferred) at an anglerelative to the upper plane of the shoe sole 28 so that only a smallerportion of the rounded side 28 a defined by the constant thickness lyingalong the surface 31 a is coplanar with the Theoretically IdealStability Plane 51. FIGS. 34C and 34C show similar embodiments whereineach engineering trade-off shown results in progressively smallerportions of rounded side 28 a, which lies along the Theoretically IdealStability Plane 51. The portion of the surface 31 a merges into theupper side surface 53 a of the naturally rounded side 28 a.

The embodiment of FIG. 34 may be desirable for portions of the shoe solewhich are less frequently used so that the additional part of the sideis used less frequently. For example, a shoe may typically roll outlaterally, in an inversion mode, to about 20° on the order of 100 timesfor each single time it rolls out to 40°. For a basketball shoe, shownin FIG. 34B, the extra stability is needed. Yet, the added shoe weightto cover that infrequently experienced range of motion is aboutequivalent to covering the frequently encounter range. Since in a racingshoe this weight might not be desirable, an engineering trade-off of thetype shown in FIG. 34D is possible. A typical athletic/jogging shoe isshown in FIG. 34C. The range of possible variations is limitless.

FIG. 35 shows the Theoretically Ideal Stability Plane 51 in definingembodiments of the shoe sole having differing tread or cleat patterns.Thus, FIG. 35 illustrates that the invention is applicable to shoe soleshaving conventional bottom treads. Accordingly, FIG. 35A is similar toFIG. 34B further including a tread portion 60, while FIG. 35B is alsosimilar to FIG. 34B wherein the sole includes a cleated portion 61. Thesurface 63 to which the cleat bases are affixed should preferably be onthe same plane and parallel the Theoretically Ideal Stability Plane 51,since in soft ground that surface rather than the cleats becomeload-bearing. The embodiment in FIG. 35C is similar to FIG. 34C showingstill an alternative tread construction 62. In each case, theload-bearing outer surface of the tread or cleat pattern 60-62 liesalong the Theoretically Ideal Stability Plane 51.

FIG. 36 illustrates in a curve 70 the range of side to sideinversion/eversion motion of the ankle center of gravity 71 from theshoe shown in frontal plane cross-section at the ankle. Thus, in astatic case where the center of gravity 71 lies at approximately themid-point of the sole, and assuming that the shoe inverts or everts from0° to 20° to 40°, as shown in progressions 36A, 36B and 36C, the locusof points of motion for the center of gravity thus defines the curve 70wherein the center of gravity 71 maintains a steady level motion with novertical component through 40° of inversion or eversion. For theembodiment shown, the shoe sole stability equilibrium point is at 28°(at point 74) and in no case is there a pivoting edge to define arotation point. The inherently superior side to side stability of thedesign provides pronation control (or eversion), as well as lateral (orinversion) control. In marked contrast to conventional shoe soledesigns, this shoe design creates virtually no abnormal torque to resistnatural inversion/eversion motion or to destabilize the ankle joint.

FIG. 37 thus compares the range of motion of the center of gravity forthe invention, as shown in curve 70, in comparison to curve 80 for theconventional wide heel flare and a curve 82 for a narrow rectangle thewidth of a human heel. Since the shoe stability limit is 28° in theinverted mode, the shoe sole is stable at the 20° approximate bare footinversion limit. That factor, and the broad base of support rather thanthe sharp bottom edge of the prior art, make the rounded design stableeven in the most extreme case as shown in FIGS. 36A-36C and permit theinherent stability of the bare foot to dominate without interference,unlike existing designs, by providing constant, unvarying shoe solethickness in frontal plane cross sections. The stability superiority ofthe rounded side design is thus clear when observing how much flatterits center of gravity curve 70 is than in existing popular wide flaredesign 80. The curve demonstrates that the rounded side design hassignificantly more efficient natural 7° inversion/eversion motion thanthe narrow rectangle design the width of a human heel, and very muchmore efficient than the conventional wide flare design. At the sametime, the rounded side design is more stable in extremis than eitherconventional design because of the absence of destabilizing torque.

FIGS. 38A-38D illustrate, in frontal plane cross sections, the naturallyrounded sides design extended to the other natural contours underneaththe load-bearing foot, such as the main longitudinal arch, themetatarsal (or forefoot) arch, and the ridge between the heads of themetatarsals (forefoot) and the heads of the distal phalanges (toes). Asshown, the shoe sole thickness remains constant as the rounded of theshoe sole follows that of the sides and bottom of the load-bearing foot.FIG. 38E shows a sagittal plane cross section of the shoe soleconforming to the rounded of the bottom of the load-bearing foot, withthickness varying according to the heel lift 38. FIG. 38F shows ahorizontal plane top view of the left foot that shows the areas 85 ofthe shoe sole that correspond to the flattened portions of the foot solethat are in contact with the ground when load-bearing. Rounded lines 86and 87 show approximately the relative height of the shoe sole contoursabove the flattened load-bearing areas 85 but within roughly theperipheral extent 35 of the upper surface of sole 30 shown in FIG. 30. Ahorizontal plane bottom view (not shown) of FIG. 38F would be the exactreciprocal or converse of FIG. 38F (i.e. peaks and valleys contourswould be exactly reversed).

FIGS. 39A-39D show, in frontal plane cross sections, the fully roundedshoe sole design extended to the bottom of the entire non-load-bearingfoot. FIG. 39E shows a sagittal plane cross section. The shoe solecontours underneath the foot are the same as FIGS. 38A-38E except thatthere are no flattened areas corresponding to the flattened areas of theload-bearing foot. The exclusively rounded contours of the shoe solefollow those of the unloaded foot. A heel lift 38 and a midsole andoutersole 39, the same as that of FIG. 38, is incorporated in thisembodiment, but is not shown in FIG. 39.

FIG. 40 shows the horizontal plane top view of the left footcorresponding to the fully rounded design described in FIGS. 39A-39E,but abbreviated along the sides to only essential structural support andpropulsion elements. Shoe sole material density can be increased in theunabbreviated essential elements to compensate for increased pressureloading there. The essential structural support elements are the baseand lateral tuberosity of the calcaneus 95, the heads of the metatarsals96, and the base of the fifth metatarsal 97. They must be supported bothunderneath and to the outside for stability. The essential propulsionelement is the head of first distal phalange 98. The medial (inside) andlateral (outside) sides supporting the base of the calcaneus are shownin FIG. 40 oriented roughly along either side of the horizontal planesubtalar ankle joint axis, but can be located also more conventionallyalong the longitudinal axis of the shoe sole. FIG. 40 shows that thenaturally rounded stability sides need not be used except in theidentified essential areas. Weight savings and flexibility improvementscan be made by omitting the non-essential stability sides. Rounded lines85 through 89 show approximately the relative height of the shoe solecontours within roughly the peripheral extent 35 of the undeformed uppersurface of shoe sole 30 shown in FIG. 17. A horizontal plane bottom view(not shown) of FIG. 40 would be the exact reciprocal or converse of FIG.40 (i.e. peaks and valleys contours would be exactly reversed).

FIG. 41A shows a development of street shoes with naturally rounded solesides incorporating features according to the present invention. FIG.41A develops a Theoretically Ideal Stability Plane 51, as describedabove, for such a street shoe, wherein the thickness of the naturallyrounded sides equals the shoe sole thickness. The resulting street shoewith a correctly rounded sole is thus shown in frontal plane heel crosssection in FIG. 41A, with side edges perpendicular to the ground, as istypical. FIG. 41B shows a similar street shoe with a fully roundeddesign, including the bottom of the sole. Accordingly, the invention canbe applied to an unconventional heel lift shoe, like a simple wedge, orto the most conventional design of a typical walking shoe with its heelseparated from the forefoot by a hollow under the instep. The inventioncan be applied just at the shoe heel or to the entire shoe sole. Withthe invention, as so applied, the stability and natural motion of anyexisting shoe design, except high heels or spike heels, can besignificantly improved by the naturally rounded shoe sole design.

FIG. 42 shows a non-optimal but interim or low cost approach to shoesole construction, whereby the midsole 148 and heel lift 38 are producedconventionally, or nearly so (at least leaving the midsole bottomsurface flat, though the sides can be rounded), while the bottom orouter sole 149 includes most or all of the special contours of thedesign. Not only would that completely or mostly limit the specialcontours to the bottom sole, which would be molded specially, it wouldalso ease assembly, since two flat surfaces of the bottom of the midsoleand the top of the bottom sole could be mated together with lessdifficulty than two rounded surfaces, as would be the case otherwise.

The advantage of this approach is seen in the naturally rounded designexample illustrated in FIG. 42A, which shows some contours on therelatively softer midsole sides, which are subject to less wear butbenefit from greater traction for stability and ease of deformation,while the relatively harder rounded bottom sole provides good wear forthe load-bearing areas.

FIG. 42B shows in a quadrant side design the concept applied toconventional street shoe heels, which are usually separated from theforefoot by a hollow instep area under the main longitudinal arch.

FIG. 42C shows in frontal plane cross-section the concept applied to thequadrant sided or single plane design and indicating in FIG. 42D in theshaded area 129 of the bottom sole that portion which should behoneycombed (axis on the horizontal plane) to reduce the density of therelatively hard outer sole to that of the midsole material to providefor relatively uniform shoe density.

Generally, insoles or sock liners should be considered structurally andfunctionally as part of the shoe sole, as should any shoe materialbetween foot and ground, like the bottom of the shoe upper in aslip-lasted shoe or the board in a board-lasted shoe.

FIG. 43 shows in a real illustration a foot 27 in position for a newbiomechanical test that is the basis for the discovery that anklesprains are in fact unnatural for the bare foot. The test simulates alateral ankle sprain, where the foot 27—on the ground 43—rolls or tiltsto the outside, to the extreme end of its normal range of motion, whichis usually about 20 degrees at the outer surface of the foot 29, asshown in a rear view of a bare (right) heel in FIG. 43. Lateral(inversion) sprains are the most common ankle sprains, accounting forabout three-fourths of all ankle sprains.

The especially novel aspect of the testing approach is to perform theankle spraining simulation while standing stationary. The absence offorward motion is the key to the dramatic success of the test becauseotherwise it is impossible to recreate for testing purposes the actualfoot and ankle motion that occurs during a lateral ankle sprain, andsimultaneously to do it in a controlled manner, while at normal runningspeed or even jogging slowly, or walking. Without the critical controlachieved by slowing forward motion all the way down to zero, any testsubject would end up with a sprained ankle.

That is because actual running in the real world is dynamic and involvesa repetitive force maximum of three times one's full body weight foreach footstep, with sudden peaks up to roughly five or six times forquick stops, missteps, and direction changes, as might be experiencedwhen spraining an ankle. In contrast, in the static simulation test, theforces are tightly controlled and moderate, ranging from no force at allup to whatever maximum amount that is comfortable.

The Stationary Sprain Simulation Test (SSST) consists simply of standingstationary with one foot bare and the other shod with any shoe. Eachfoot alternately is carefully tilted to the outside up to the extremeend of its range of motion, simulating a lateral ankle sprain.

The SSST clearly identifies what can be no less than a fundamentalproblem in existing shoe design. It demonstrates conclusively thatnature's biomechanical system, the bare foot, is far superior instability to man's artificial shoe design. Unfortunately, it alsodemonstrates that the shoe's severe instability overpowers the naturalstability of the human foot and synthetically creates a combinedbiomechanical system that is artificially unstable. The shoe is the weaklink.

The test shows that the bare foot is inherently stable at theapproximate 20 degree end of normal joint range because of the wide,steady foundation the bare heel 29 provides the ankle joint, as seen inFIG. 43. In fact, the area of physical contact of the bare heel 29 withthe ground 43 is not much less when tilted all the way out to 20 degreesas when upright at 0 degrees.

The SSST provides a natural yardstick, totally missing until now, todetermine whether any given shoe allows the foot within it to functionnaturally. If a shoe cannot pass this simple test, it is positive proofthat a particular shoe is interfering with natural foot and anklebiomechanics. The only question is the exact extent of the interferencebeyond that demonstrated by the SSST.

Conversely, the applicant's designs employ shoe soles thick enough toprovide cushioning (thin-soled and heel-less moccasins do pass the test,but do not provide cushioning and only moderate protection) andnaturally stable performance, like the bare foot, in the SSST.

FIG. 44 shows that, in complete contrast the foot equipped with aconventional athletic shoe, designated generally by the referencenumeral 20 and having an upper 21, though initially very stable whileresting completely flat on the ground, becomes immediately unstable whenthe shoe sole 22 is tilted to the outside. The tilting motion lifts fromcontact with the ground all of the shoe sole 22 except the artificiallysharp edge of the bottom outside corner. The shoe sole instabilityincreases the farther the foot is rolled laterally. Eventually, theinstability induced by the shoe itself is so great that the normalload-bearing pressure of full body weight would actively force an anklesprain, if not controlled. The abnormal tilting motion of the shoe doesnot stop at the bare foot's natural 20 degree limit, as can be seen fromthe 45 degree tilt of the shoe heel in FIG. 44.

That continued outward rotation of the shoe past 20 degrees causes thefoot to slip within the shoe, shifting its position within the shoe tothe outside edge, further increasing the shoe's structural instability.The slipping of the foot within the shoe is caused by the naturaltendency of the foot to slide down the typically flat surface of thetilted shoe sole; the more the tilt, the stronger the tendency. The heelis shown in FIG. 44 because of its primary importance in sprains due toits direct physical connection to the ankle ligaments that are torn inan ankle sprain and also because of the heel's predominant role withinthe foot in bearing body weight.

It is easy to see in the two figures, FIGS. 43 and 44, how totallydifferent the physical shape of the natural bare foot is compared to theshape of the artificial, conventional shoe sole. It is strikingly oddthat the two objects, which apparently both have the same biomechanicalfunction, have completely different physical shapes. Moreover, the shoesole clearly does not deform the same way the human foot sole does,primarily as a consequence of its dissimilar shape.

FIGS. 45A-45C illustrate clearly the principle of natural deformation asit applies to the applicant's designs, even though design diagrams likethose preceding are normally shown in an ideal state, without anyfunctional deformation, obviously to show their exact shape for properconstruction. That natural structural shape, with its roundedparalleling the foot, enables the shoe sole to deform naturally like thefoot. The natural deformation feature creates such an importantfunctional advantage it will be illustrated and discussed here fully.Note in the figures that even when the shoe sole shape is deformed, theconstant shoe sole thickness in the frontal plane feature of theinvention is maintained.

FIG. 45A shows upright, unloaded and therefore undeformed the fullyrounded shoe sole design indicated in FIG. 15 above. FIG. 45A shows afully rounded shoe sole design that follows the natural rounded of allof the foot sole, the bottom as well as the sides. The fully roundedshoe sole assumes that the resulting slightly rounded bottom whenunloaded will deform under load as shown in FIG. 45B and flatten just asthe human foot bottom is slightly rounded unloaded but flattens underload, like FIG. 14 above. Therefore, the shoe sole material must be ofsuch composition as to allow the natural deformation following that ofthe foot. The design applies particularly to the heel, but to the restof the shoe sole as well. By providing the closest possible match to thenatural shape of the foot, the fully rounded design allows the foot tofunction as naturally as possible. Under load, FIG. 45A would deform byflattening to look essentially like FIG. 45B.

FIGS. 45A and 45B show in frontal plane cross-section the TheoreticallyIdeal Stability Plane 51 which is also theoretically ideal for efficientnatural motion of all kinds, including running, jogging or walking. Forany given individual, the Theoretically Ideal Stability Plane 51 isdetermined, first, by the desired shoe sole thickness (s) in a frontalplane cross section, and, second, by the natural shape of theindividual's foot surface 29.

For the case shown in FIG. 45B, the Theoretically Ideal Stability Plane51 for any particular individual (or size average of individuals) isdetermined, first, by the given frontal plane cross-section shoe solethickness (s); second, by the natural shape of the individual's foot;and, third, by the frontal plane cross section width of the individual'sload-bearing footprint which is defined as the upper surface of the shoesole that is in physical contact with and supports the human foot sole.

FIG. 45B shows the same fully rounded design when upright, under normalload (body weight) and therefore deformed naturally in a manner veryclosely paralleling the natural deformation under the same load of thefoot. An almost identical portion of the foot sole that is flattened indeformation is also flattened in deformation in the shoe sole. FIG. 45Cshows the same design when tilted outward 20 degrees laterally, thenormal bare foot limit; with virtually equal accuracy it shows theopposite foot tilted 20 degrees inward, in fairly severe pronation. Asshown, the deformation of the shoe sole 28 again very closely parallelsthat of the foot, even as it tilts. Just as the area of foot contact isalmost as great when tilted 20 degrees, the flattened area of thedeformed shoe sole is also nearly the same as when upright.Consequently, the bare foot fully supported structurally and its naturalstability is maintained undiminished, regardless of shoe tilt. In markedcontrast, a conventional shoe, shown in FIG. 2, makes contact with theground with only its relatively sharp edge when tilted and is thereforeinherently unstable.

The capability to deform naturally is a design feature of theapplicant's naturally rounded shoe sole designs, whether fully roundedor rounded only at the sides, though the fully rounded design is mostoptimal and is the most natural, general case, assuming shoe solematerial such as to allow natural deformation. It is an importantfeature because, by following the natural deformation of the human foot,the naturally deforming shoe sole can avoid interfering with the naturalbiomechanics of the foot and ankle.

FIG. 45C also represents with reasonable accuracy a shoe sole designcorresponding to FIG. 45B, a naturally rounded shoe sole with aconventional built-in flattening deformation, as in FIG. 14 above,except that design would have a slight crimp at 146. Seen in this light,the naturally rounded side design in FIG. 45B is a more conventional,conservative design that is a special case of the more generally fullyrounded design in FIG. 45A, which is the closest to the natural form ofthe foot, but the least conventional. The natural deformation of theapplicant's shoe sole design follows that of the foot very closely sothat both provide a nearly equal flattened base to stabilize the foot.

FIG. 46 shows the preferred relative density of the shoe sole, includingthe insole as a part, in order to maximize the shoe sole's ability todeform naturally following the natural deformation of the foot sole.Regardless of how many shoe sole layers (including insole) orlaminations of differing material densities and flexibility are used intotal, the softest and most flexible material 147 should be closest tothe foot sole, with a progression through less soft 148, such as amidsole or heel lift, to the firmest and least flexible 149 at theoutermost shoe sole layer, the bottom sole. This arrangement helps toavoid the unnatural side lever arm/torque problem mentioned in theprevious several figures. That problem is most severe when the shoe soleis relatively hard and nondeforming uniformly throughout the shoe sole,like most conventional street shoes, since hard material transmits thedestabilizing torque most effectively by providing a rigid lever arm.

The relative density shown in FIG. 46 also helps to allow the shoe soleto duplicate the same kind of natural deformation exhibited by the barefoot sole in FIG. 43, since the shoe sole layers closest to the foot,and therefore with the most severe contours have to deform the most inorder to flatten like the barefoot and consequently need to be soft todo so easily. This shoe sole arrangement also replicates roughly thenatural bare foot, which is covered with a very tough “Seri boot” outersurface (protecting a softer cushioning interior of fat pads) amongprimitive barefoot populations.

Finally, the use of natural relative density as indicated in this figurewill allow more anthropomorphic embodiments of the applicant's designs(right and left sides of FIG. 46 show variations of different degrees)with sides going higher around the side rounded of the foot and therebyblending more naturally with the sides of the foot. These conformingsides will not be effective as destabilizing lever arms because the shoesole material there would be soft and unresponsive in transmittingtorque, since the lever arm will bend.

As a point of clarification, the forgoing principle of preferredrelative density refers to proximity to the foot and is not inconsistentwith the term “uniform density” used in conjunction with certainembodiments of applicant's invention. Uniform shoe sole density ispreferred strictly in the sense of preserving even and natural supportto the foot like the ground provides, so that a neutral starting pointcan be established, against which so-called improvements can bemeasured. The preferred uniform density is in marked contrast to thecommon practice in athletic shoes today, especially those beyond cheapor “bare bones” models, of increasing or decreasing the density of theshoe sole, particularly in the midsole, in various areas underneath thefoot to provide extra support or special softness where believednecessary. The same effect is also created by areas either supported orunsupported by the tread pattern of the bottom sole. The most commonexample of this practice is the use of denser midsole material under theinside portion of the heel, to counteract excessive pronation.

FIG. 47 illustrates that the applicant's naturally rounded shoe solesides can be made to provide a fit so close as to approximate a customfit. By molding each mass-produced shoe size with sides that are bent insomewhat from the position 29 they would normally be in to conform tothat standard size shoe last, the shoe soles so produced will verygently hold the sides of each individual foot exactly. Since the shoesole is designed as described in connection with FIG. 46 to deformeasily and naturally like that of the bare foot, it will deform easilyto provide this designed-in custom fit. The greater the flexibility ofthe shoe sole sides, the greater the range of individual foot sizevariations can be custom fit by a standard size. This approach appliesto the fully rounded design described here in FIG. 45A and in FIG. 15above, which would be even more effective than the naturally roundedsides design shown in FIG. 47.

Besides providing a better fit, the intentional undersizing of theflexible shoe sole sides of FIG. 47 allows for a simplified designutilizing a geometric approximation of the true actual rounded of thehuman. This geometric approximation is close enough to provide a virtualcustom fit, when compensated for by the flexible undersizing fromstandard shoe lasts described above.

FIG. 48 illustrates a fully rounded design, but abbreviated along thesides to only essential structural stability and propulsion shoe soleelements as shown in FIG. 11G-L above combined with freely articulatingstructural elements underneath the foot. The unifying concept is that,on both the sides and underneath the main load-bearing portions of theshoe sole, only the important structural (i.e. bone) elements of thefoot should be supported by the shoe sole, if the natural flexibility ofthe foot is to be paralleled accurately in shoe sole flexibility, sothat the shoe sole does not interfere with the foot's natural motion. Ina sense, the shoe sole should be composed of the same main structuralelements as the foot and they should articulate with each other just asdo the main joints of the foot.

FIG. 48E shows the horizontal plane bottom view of the right footcorresponding to the fully rounded design previously described, butabbreviated along the sides to only essential structural support andpropulsion elements. Shoe sole material density can be increased in theunabbreviated essential elements to compensate for increased pressureloading there. The essential structural support elements are the baseand lateral tuberosity of the calcaneus 95, the heads of the metatarsals96, and the base of the fifth metatarsal 97 (and the adjoining cuboid insome individuals). They must be supported both underneath and to theoutside edge of the foot for stability. The essential propulsion elementis the head of the first distal phalange 98. FIG. 48 shows that thenaturally rounded stability sides need not be used except in theidentified essential areas. Weight savings and flexibility improvementscan be made by omitting the non-essential stability sides.

The design of the portion of the shoe sole directly underneath the footshown in FIG. 48 allows for unobstructed natural inversion/eversionmotion of the calcaneus by providing maximum shoe sole flexibilityparticularly between the base of the calcaneus 125 (heel) and themetatarsal heads 126 (forefoot) along an axis 124. An unnatural torsionoccurs about that axis if flexibility is insufficient so that aconventional shoe sole interferes with the inversion/eversion motion byrestraining it. The object of the design is to allow the relatively moremobile (in inversion and eversion) calcaneus to articulate freely andindependently from the relatively more fixed forefoot instead of thefixed or fused structure or lack of stable structure between the two inconventional designs. In a sense, freely articulating joints are createdin the shoe sole that parallel those of the foot. The design is toremove nearly all of the shoe sole material between the heel and theforefoot, except under one of the previously described essentialstructural support elements, the base of the fifth metatarsal 97. Anoptional support for the main longitudinal arch 121 may also be retainedfor runners with substantial foot pronation, although it would not benecessary for many runners.

The forefoot can be subdivided (not shown) into its component essentialstructural support and propulsion elements, the individual heads of themetatarsal and the heads of the distal phalanges, so that each majorarticulating joint set of the foot is paralleled by a freelyarticulating shoe sole support propulsion element, an anthropomorphicdesign; various aggregations of the subdivision are also possible.

The design in FIG. 48 features an enlarged structural support at thebase of the fifth metatarsal in order to include the cuboid, which canalso come into contact with the ground under arch compression in someindividuals. In addition, the design can provide general side support inthe heel area, as in FIG. 48E or alternatively can carefully orient thestability sides in the heel area to the exact positions of the lateralcalcaneal tuberosity 108 and the main base of the calcaneus 109, as inFIG. 48E (showing heel area only of the right foot). FIGS. 48A-48D showfrontal plane cross sections of the left shoe and FIG. 48E shows abottom view of the right foot, with flexibility axes 122, 124, 111, 112and 113 indicated. FIG. 48F shows a sagittal plane cross section showingthe structural elements joined by a very thin and relatively soft uppermidsole layer. FIGS. 48G and 48H show similar cross sections withslightly different designs featuring durable fabric only (slip-lastedshoe), or a structurally sound arch design, respectively. FIG. 48I showsa side medial view of the shoe sole.

FIG. 48J shows a simple interim or low cost construction for thearticulating shoe sole support element 95 for the heel (showing the heelarea only of the right foot); while it is most critical and effectivefor the heel support element 95, it can also be used with the otherelements, such as the base of the fifth metatarsal 97 and the long arch121. The heel sole element 95 shown can be a single flexible layer or alamination of layers. When cut from a flat sheet or molded in thegeneral pattern shown, the outer edges can be easily bent to follow thecontours of the foot, particularly the sides. The shape shown allows aflat or slightly rounded heel element 95 to be attached to a highlyrounded shoe upper or very thin upper sole layer like that shown in FIG.48F. Thus, a very simple construction technique can yield a highlysophisticated shoe sole design. The size of the center section 119 canbe small to conform to a fully or nearly fully rounded design or largerto conform to a rounded sides design, where there is a large flattenedsole area under the heel. The flexibility is provided by the removeddiagonal sections, the exact proportion of size and shape can vary.

FIG. 49 shows use of the Theoretically Ideal Stability Plane 51 conceptto provide natural stability in negative heel shoe soles that are lessthick in the heel area than in the rest of the shoe sole; specifically,a negative heel version of the naturally rounded sides conforming to aload-bearing foot design shown in FIG. 14 above.

FIGS. 49A, 49B, and 49C represent frontal plane cross sections takenalong the forefoot, at the base of the fifth metatarsal, and at theheel, thus illustrating that the shoe sole thickness is constant at eachfrontal plane cross section, even though that thickness varies fromfront to back, due to the sagittal plane variation 40 (shown hatched)causing a lower heel than forefoot, and that the thickness of thenaturally rounded sides is equal to the shoe sole thickness in each FIG.49A-49C cross-section. Moreover, in FIG. 49D, a horizontal planeoverview or top view of the left foot sole, it can be seen that thehorizontal rounded of the sole follows the preferred principle inmatching, as nearly as practical, the rough footprint of theload-bearing foot sole.

The abbreviation of essential structural support elements can also beapplied to negative heel shoe soles such as that shown in FIG. 49 anddramatically improves their flexibility. Negative heel shoe soles suchas FIG. 49 can also be modified by inclusion of aspects of the otherembodiments disclosed herein.

FIG. 50 shows, in FIGS. 50A-50D, possible sagittal plane shoe solethickness variations for negative heel shoes. The hatched areas indicatethe forefoot lift or wedge 40. At each point along the shoe soles seenin sagittal plane cross sections, the thickness varies as shown in FIGS.50A-50D, while the thickness of the naturally rounded sides 28 a, asmeasured in the frontal plane, equal and therefore vary directly withthose sagittal plane thickness variations. FIG. 50A shows the sameembodiment as FIG. 49.

FIG. 51 shows the application of the Theoretically Ideal Stability Planeconcept in flat shoe soles that have no heel lift to provide for naturalstability, maintaining the same thickness throughout, with roundedstability sides abbreviated to only essential structural supportelements to provide the shoe sole with natural flexibility parallelingthat of the human foot.

FIGS. 51A, 51B, and 51C represent frontal plane cross-sections takenalong the forefoot, at the base of the fifth metatarsal, and at theheel, thus illustrating that the shoe sole thickness is constant at eachfrontal plane cross section, while constant in the sagittal plane fromfront to back, so that the heel and forefoot have the same shoe solethickness, and that the thickness of the naturally rounded sides isequal to the shoe sole thickness in each FIG. 51A-51C cross-section.Moreover, in FIG. 51C, a horizontal plane overview or top view of theleft foot sole, it can be seen that the horizontal rounded of the solefollows the preferred principle in matching, as nearly as practical, therough footprint of the load-bearing foot sole. FIG. 51E, a sagittalplane cross section, shows that shoe sole thickness is constant in thatplane.

FIG. 51 shows the applicant's prior invention of rounded sidesabbreviated to essential structural elements, as applied to a flat shoesole. FIG. 51 shows the horizontal plane top view of fully rounded shoesole of the left foot abbreviated along the sides to only essentialstructural support and propulsion elements (shown hatched). Shoe solematerial density can be increased in the unabbreviated essentialelements to compensate for increased pressure loading there. Theessential structural support elements are the base and lateraltuberosity of the calcaneus 95, the heads of the metatarsals 96, andbase of the fifth metatarsal 97. They must be supported both underneathand to the outside for stability. The essential propulsion element isthe head of the first distal phalange 98.

The medial (inside) and lateral (outside) sides supporting the base andlateral tuberosity of the calcaneus are shown in FIG. 51 oriented in aconventional way along the longitudinal axis of the shoe sole, in orderto provide direct structural support to the base and lateral tuberosityof the calcaneus, but can be located also along either side of thehorizontal plane subtalar ankle joint axis. FIG. 51 shows that thenaturally rounded stability sides need not be used except in theidentified essential areas. Weight savings and flexibility improvementscan be made by omitting the non-essential stability sides. A horizontalplane bottom view (not shown) of FIG. 51 would be the exact reciprocalor converse of FIG. 51 with the peaks and valleys contours exactlyreversed.

Flat shoe soles such as FIG. 51 can also be modified by inclusion ofaspects of the other embodiments disclosed herein.

Central midsole section 188 and upper section 187 in FIG. 12 mustfulfill a cushioning function which frequently calls for relatively softmidsole material. The shoe sole thickness effectively decreases in theFIG. 12 embodiment when the soft central section is deformed underweight-bearing pressure to a greater extent than the relatively firmersides.

In order to control this effect, it is necessary to measure it. What isrequired is a methodology of measuring a portion of a static shoe soleat rest that will indicate the resultant thickness under deformation. Asimple approach is to take the actual least distance thickness at anypoint and multiply it times a factor for deformation or “give”, which istypically measured in durometers (on Shore A scale), to get a resultingthickness under a standard deformation load. Assuming a linearrelationship (which can be adjusted empirically in practice), thismethod would mean that a shoe sole midsection of 1 inch thickness and afairly soft 30 durometer would be roughly functionally equivalent underequivalent load-bearing deformation to a shoe midsole section of ½ inchand a relatively hard 60 durometer; they would both equal a factor of 30inch-durometers. The exact methodology can be changed or improvedempirically, but the basic point is that static shoe sole thicknessneeds to have a dynamic equivalent under equivalent loads, depending onthe density of the shoe sole material.

Since the Theoretically Ideal Stability Plane 51 has already beengenerally defined in part as having a constant frontal plane thicknessand preferring a uniform material density to avoid arbitrarily alteringnatural foot motion, it is logical to develop a non-static definitionthat includes compensation for shoe sole material density. TheTheoretically Ideal Stability Plane 51 defined in dynamic terms wouldalter constant thickness to a constant multiplication product ofthickness times density.

Using this restated definition of the Theoretically Ideal StabilityPlane 51 presents an interesting design possibility: the somewhatextended width of shoe sole sides that are required under the staticdefinition of the Theoretically Ideal Stability Plane 51 could bereduced by using a higher density midsole material in the naturallyrounded sides.

FIG. 52 shows, in frontal plane cross section at the heel, the use of ahigh density (d′) midsole material on the naturally rounded sides and alow density (d) midsole material everywhere else to reduce side width.To illustrate the principle, it was assumed in FIG. 52 that density (d′)is twice that of density (d), so the effect is somewhat exaggerated, butthe basic point is that shoe sole width can be reduced significantly byusing the Theoretically Ideal Stability Plane 51 with a definition ofthickness that compensates for dynamic force loads. In the FIG. 52example, about one fourth of an inch in width on each side is savedunder the revised definition, for a total width reduction of one halfinch, while rough functional equivalency should be maintained, as if thefrontal plane thickness and density were each unchanging.

As shown in FIG. 52, the boundary between sections of different densityis indicated by the line 45 and the line 51′ parallel to 51 at half thedistance from the outer surface of the foot 29.

Note that the design in FIG. 52 uses low density midsole material, whichis effective for cushioning, throughout that portion of the shoe solethat would be directly load-bearing from roughly 10 degrees of inversionto roughly 10 degrees eversion, the normal range of maximum motionduring athletics; the higher density midsole material is tapered in fromroughly 10 degrees to 30 degrees on both sides, at which rangescushioning is less critical than providing stabilizing support.

FIG. 53 show the footprints of the natural barefoot sole and shoe sole.The footprints are the areas of contact between the bottom of the footor shoe sole and the flat, horizontal plane of the ground, under normalbody weight-bearing conditions. FIG. 53A shows a typical right footprintoutline 37 when the foot is upright with its sole flat on the ground.

FIG. 53B shows the footprint outline 17 of the same foot when tilted out20 degrees to about its normal limit; this footprint corresponds to theposition of the foot shown in FIG. 43 above. Critical to the inherentnatural stability of the barefoot is that the area of contact betweenthe heel and the ground is virtually unchanged, and the area under thebase of the fifth metatarsal and cuboid is narrowed only slightly.Consequently, the barefoot maintains a wide base of support even whentilted to its most extreme lateral position.

The major difference shown in FIG. 53B is clearly in the forefoot, whereall of the heads of the first through fourth metatarsals and theircorresponding phalanges no longer make contact with the ground. Of theforefoot, only the head of the fifth metatarsal continues to makecontact with the ground, as does its corresponding phalange, althoughthe phalange does so only slightly. The forefoot motion of the forefootis relatively great compared to that of the heel.

FIG. 53C shows a shoe sole print outline of a shoe sole of the same sizeas the bare foot in FIGS. 53A & 53B when tilted out 20 degrees to thesame position as FIG. 53B; this position of the shoe sole corresponds tothat shown in FIG. 44 above. The shoe sole maintains only a very narrowbottom edge in contact with the ground, an area of contact many timesless than the bare foot.

FIG. 54 shows two footprints like footprint 37 in FIG. 53A of a barefoot upright and footprint 17 in FIG. 53B of a bare foot tilted out 20degrees, but showing also their actual relative positions to each otheras the foot rolls outward from upright to tilted out 20 degrees. Thebare foot tilted footprint is shown hatched. The position of tiltedfootprint 17 so far to the outside of upright footprint 37 demonstratesthe requirement for greater shoe sole width on the lateral side of theshoe to keep the foot from simply rolling off of the shoe sole; thisproblem is in addition to the inherent problem caused by the rigidity ofthe conventional shoe sole. The footprints are of a high arched foot.

FIG. 55 shows the applicant's invention of shoe sole with a lateralstability sipe 11 in the form of a vertical slit. The lateral stabilitysipe allows the shoe sole to flex in a manner that parallels the footsole, as seen is FIGS. 53 & 54. The lateral stability sipe 11 allows theforefoot of the shoe sole to pivot off the ground with the wear'sforefoot when the wearer's foot rolls out laterally. At the same time,it allows the remaining shoe sole to remain flat on the ground under thewearer's load-bearing tilted footprint 17 in order to provide a firm andnatural base of structural support to the wearer's heel, his fifthmetatarsal base and head, as well as cuboid and fifth phalange andassociated softer tissues. In this way, the lateral stability sipeprovides the wearer of even a conventional shoe sole with lateralstability like that of the bare foot. All types of shoes can bedistinctly improved with this invention, even women's high heeled shoes.

With the lateral stability sipe, the natural supination of the foot,which is its outward rotation during load-bearing, can occur withgreatly reduced obstruction. The functional effect is analogous toproviding a car with independent suspension, with the axis alignedcorrectly. At the same time, the principle load-bearing structures ofthe foot are firmly supported with no sipes directly underneath.

FIG. 55A is a top view of a conventional shoe sole with a correspondingoutline of the wearer's footprint superimposed on it to identify theposition of the lateral stability sipe 11, which is fixed relative tothe wearer's foot, since it removes the obstruction to the foot'snatural lateral flexibility caused by the conventional shoe sole.

With the lateral stability sipe 11 in the form of a vertical slit, whenthe foot sole is upright and flat, the shoe sole provides firmstructural support as if the sipe were not there. No rotation beyond theflat position is possible with a sipe in the form of a slit, since theshoe sole on each side of the slit prevents further motion.

Many variations of the lateral stability sipe 11 are possible to providethe same unique functional goal of providing shoe sole flexibility alongthe general axis shown in FIG. 55. For example, the slit can be ofvarious depths depending on the flexibility of the shoe sole materialused; the depth can be entirely through the shoe sole, so long as someflexible material acts as a joining hinge, like the cloth of a fullylasted shoe, which covers the bottom of the foot sole, as well as thesides. The slits can be multiple, in parallel or askew. They can beoffset from vertical. They can be straight lines, jagged lines, curvedlines or discontinuous lines.

Although slits are preferred, other sipe forms such as channels orvariations in material densities as described above can also be used,though many such forms will allow varying degrees of further pronationrotation beyond the flat position, which may not be desirable, at leastfor some categories of runners. Other methods in the existing art can beused to provide flexibility in the shoe sole similar to that provided bythe lateral stability sipe along the axis shown in FIG. 55.

The axis shown in FIG. 55 can also vary somewhat in the horizontalplane. For example, the footprint outline 37 shown in FIG. 55 ispositioned to support the heel of a high arched foot; for a low archedfoot tending toward excessive pronation, the medial origin 14 of thelateral stability sipe would be moved forward to accommodate the moreinward or medial position of pronator's heel. The axis position can alsobe varied for a corrective purpose tailored to the individual orcategory of individual: the axis can be moved toward the heel of arigid, high arched foot to facilitate pronation and flexibility, and theaxis can be moved away from the heel of a flexible, low arched foot toincrease support and reduce pronation.

It should be noted that various forms of firm heel counters and motioncontrol devices in common use can interfere with the use of the lateralstability sipe by obstructing motion along its axis; therefore, the useof such heel counters and motion control devices should be avoided. Thelateral stability sipe may also compensate for shoe heel-induced outwardknee cant.

FIG. 55B is a cross section of the shoe sole 22 with lateral stabilitysipe 11. The shoe sole thickness is constant but could vary as do manyconventional and unconventional shoe soles known to the art. The shoesole could be conventionally flat like the ground or conform to theshape of the wearer's foot.

FIG. 55C is a top view like FIG. 55A, but showing the print of the shoesole with a lateral stability sipe when the shoe sole is tilted outward20 degrees, so that the forefoot of the shoe sole is not longer incontact with the ground, while the heel and the lateral section doremain flat on the ground.

FIG. 56 shows a conventional shoe sole with a medial stability sipe 12that is like the lateral sipe 11, but with a purpose of providingincreased medial or pronation stability instead of lateral stability;the head of the first metatarsal and the first phalange are includedwith the heel to form a medial support section inside of a flexibilityaxis defined by the medial stability sipe 12. The medial stability sipe12 can be used alone, as shown, or together with the lateral stabilitysipe 11, which is not shown.

FIG. 57 shows footprints 37 and 17, like FIG. 54, of a right barefootupright and tilted out 20 degrees, showing the actual relative positionsto each other as a low arched foot rolls outward from upright to tiltedout 20 degrees. The low arched foot is particularly noteworthy becauseit exhibits a wider range of motion than the FIG. 54 high arched foot,so the 20 degree lateral tilt footprint 17 is farther to the outside ofupright footprint 37. In addition, the low arched foot pronates inwardto inner footprint borders 18; the hatched area 19 is the increased areaof the footprint due to the pronation, whereas the hatched area 16 isthe decreased area due to pronation.

In FIG. 57, the lateral stability sipe 11 is clearly located on the shoesole along the inner margin of the lateral footprint 17 superimposed ontop of the shoe sole and is straight to maximize ease of flexibility.The basic FIG. 57 design can of course also be used without the lateralstability sipe 11.

A shoe sole of extreme width is necessitated by the common foot tendencytoward excessive pronation, as shown in FIG. 57, in order to providestructural support for the full range of natural foot motion, includingboth pronation and supination. Extremely wide shoe soles are mostpractical if the sides of the shoe sole are not flat as is conventionalbut rather are bent up to conform to the natural shape of the shoewearer's foot sole.

FIGS. 58A-58D shows the use of flexible and relatively inelastic fiberin the form of strands, woven or unwoven (such as pressed sheets),embedded in midsole and bottom sole material. Optimally, the fiberstrands parallel (at least roughly) the plane surface of the wearer'sfoot sole in the naturally rounded design in FIGS. 58A-58C and parallelthe flat ground in FIG. 58D, which shows a section of conventional,non-rounded shoe sole. Fiber orientations at an angle to this parallelposition will still provide improvement over conventional soles withoutfiber reinforcement, particularly if the angle is relatively small;however, very large angles or omni-directionality of the fibers willresult in increased rigidity or increased softness.

This preferred orientation of the fiber strands, parallel to the planeof the wearer's foot sole, allows for the shoe sole to deform to flattenin parallel with the natural flattening of the foot sole under pressure.At the same time, the tensile strength of the fibers resist the downwardpressure of body weight that would normally squeeze the shoe solematerial to the sides, so that the side walls of the shoe sole will notbulge out (or will do so less so). The result is a shoe sole materialthat is both flexible and firm. This unique combination of functionaltraits is in marked contrast to conventional shoe sole materials inwhich increased flexibility unavoidably causes increased softness andincreased firmness also increases rigidity. FIG. 58A is a modificationof FIG. 5A, FIG. 58B is FIG. 6 modified and FIG. 58C is FIG. 7 modified.The position of the fibers shown would be the same even if the shoe solematerial is made of one uniform material or of other layers than thoseshown here.

The use of the fiber strands, particularly when woven, providesprotection against penetration by sharp objects, much like the fiber inradial automobile tires. The fiber can be of any size, eitherindividually or in combination to form strands; and of any material withthe properties of relative inelasticity (to resist tension forces) andflexibility. The strands of fiber can be short or long, continuous ordiscontinuous. The fibers facilitate the capability of any shoe soleusing them to be flexible but hard under pressure, like the foot sole.

It should also be noted that the fibers used in both the cover ofinsoles and the Dellinger Web is knit or loosely braided rather thanwoven, which is not preferred, since such fiber strands are designed tostretch under tensile pressure so that their ability to resist sidewaysdeformation would be greatly reduced compared to non-knit fiber strandsthat are individually (or in twisted groups of yarn) woven or pressedinto sheets.

FIGS. 59A-59D are FIGS. 9A-D modified to show the use of flexibleinelastic fiber or fiber strands, woven or unwoven (such as pressed) tomake an embedded capsule shell that surrounds the cushioning compartment161 containing a pressure-transmitting medium like gas, gel, or liquid.The fibrous capsule shell could also directly envelope the surface ofthe cushioning compartment, which is easier to construct, especiallyduring assembly. FIG. 59E is a figure showing a fibrous capsule shell191 that directly envelopes the surface of a cushioning compartment 161;the shoe sole structure is not fully rounded, like FIG. 59A, butnaturally rounded, and has a flat middle portion corresponding to theflattened portion of a wearer's load-bearing foot sole.

FIG. 59F shows a unique combination of the FIGS. 9 & 10 design above.The upper surface 165 and lower surface 166 contain the cushioningcompartment 161, which is subdivided into two parts. The lower half ofthe cushioning compartment 161 is both structured and functions like thecompartment shown in FIG. 9 above. The upper half is similar to FIG. 10above but subdivided into chambers 192 that are more geometricallyregular so that construction is simpler; the structure of the chambers192 can be of honeycombed in structure. The advantage of this design isthat it copies more closely than the FIG. 9 design the actual structureof the wearer's foot sole, while being much more simple to constructthan the FIG. 10 design. Like the wearer's foot sole, the FIG. 59Fdesign would be relative soft and flexible in the lower half of thechamber 161, but firmer and more protective in the upper half, where themini-chambers 192 would stiffen quickly under load-bearing pressure.Other multi-level arrangements are also possible.

FIGS. 60A-60D show the use of embedded flexible inelastic fiber or fiberstrands, woven or unwoven, in various embodiments similar those shown inFIGS. 58A-58D. FIG. 60E is a figure showing a frontal plane crosssection of a fibrous capsule shell 191 that directly envelopes thesurface of the midsole section 188.

FIG. 61C compares the footprint made by a conventional shoe 35 with therelative positions of the wearer's right foot sole in the maximumsupination position 37 a and the maximum pronation position 37 b. FIG.61C reinforces the indication that more relative sideways motion occursin the forefoot and midtarsal areas, than in the heel area.

As shown in FIG. 61C, at the extreme limit of supination and pronationfoot motion, the base of the calcaneus 109 and the lateral calcanealtuberosity 108 roll slightly off the sides of the shoe sole outerboundary 35. However, at the same extreme limit of supination, the baseof the fifth metatarsal 97 and the head of the fifth metatarsal 94 andthe fifth distal phalange 93 all have rolled completely off the outerboundary 35 of the shoe sole.

FIG. 61D shows an overhead perspective of the actual bone structures ofthe foot.

FIG. 62 is similar to FIG. 57 above, in that it shows a shoe sole thatcovers the full range of motion of the wearer's right foot sole, with orwithout a sipe 11. However, while covering that full range of motion, itis possible to abbreviate the rounded sides of the shoe sole to only theessential structural and propulsion elements of the foot sole, aspreviously discussed herein.

FIG. 63 shows an electronic image of the relative forces present at thedifferent areas of the bare foot sole when at the maximum supinationposition shown as 37 a in FIG. 62 above; the forces were measured duringa standing simulation of the most common ankle spraining position. Themaximum force was focused at the head of the fifth metatarsal and thesecond highest force was focused at the base of the fifth metatarsal.Forces in the heel area were substantially less overall and less focusedat any specific point.

FIG. 63 indicates that, among the essential structural support andpropulsion elements shown in FIG. 40 above, there are relative degreesof importance. In terms of preventing ankle sprains, the most commonathletic injury (about two-thirds occur in the extreme supinationposition 37 a shown in FIG. 62), FIG. 63 indicates that the head of thefifth metatarsal 94 is the most critical single area that must besupported by a shoe sole in order to maintain barefoot-like lateralstability. FIG. 63 indicates that the base of the fifth metatarsal 97 isvery close to being as important. Generally, the base and the head ofthe fifth metatarsal are completely unsupported by a conventional shoesole.

FIGS. 64A-64B demonstrate a variation in the Theoretically IdealStability Plane 51. In previously described embodiments, the innersurface of the Theoretically Ideal Stability Plane 51 conforms to theshape of the wearer's foot, especially its sides, so that the innersurface of the applicant's shoe sole invention conforms to the outersurface of the wearer's foot sole, especially it sides, when measured infrontal plane or transverse plane cross sections. For illustrationpurposes, the right side of FIG. 64 explicitly illustrates such anembodiment.

The right side of FIG. 64 includes an upper shoe sole surface that iscomplementary to the shape of all or a portion the wearer's foot sole.In addition, this application describes shoe rounded sole side designswherein the inner surface of the Theoretically Ideal Stability Plane 51lies at some point between conforming or complementary to the shape ofthe wearer's foot sole, that is—roughly paralleling the foot soleincluding its side—and paralleling the flat ground; that inner surfaceof the Theoretically Ideal Stability Plane 51 becomes load-bearing incontact with the foot sole during foot inversion and eversion, which isnormal sideways or lateral motion.

Again, for illustration purposes, the left side of FIG. 64B describesshoe sole side designs wherein the lower surface of the TheoreticallyIdeal Stability Plane 51, which equates to the load-bearing surface ofthe bottom or outer shoe sole, of the shoe sole side portions is abovethe plane of the underneath portion of the shoe sole, when measured infrontal or transverse plane cross sections; that lower surface of theTheoretically Ideal Stability Plane 51 becomes load-bearing in contactwith the ground during foot inversion and eversion, which is normalsideways or lateral motion.

Although the inventions described in this application may in someinstances be less than optimal, they nonetheless distinguish over allprior art and still do provide a significant stability improvement overexisting footwear and thus provide significantly increased injuryprevention benefit compared to existing footwear.

FIG. 65 provides a means to measure the rounded shoe sole sidesincorporated in the applicant's inventions described above. FIG. 65correlates the height or extent of the rounded side portions of the shoesole with a precise angular measurement from zero to 180 degrees. Thatangular measurement corresponds roughly with the support for sidewaystilting provided by the rounded shoe sole sides of any angular amountfrom zero degrees to 180 degrees, at least for such rounded sidesproximate to any one or more or all of the essential stability orpropulsion structures of the foot, as defined above. The rounded shoesole sides as described in this application can have any angularmeasurement from zero degrees to 180 degrees.

FIGS. 66A-66F, FIG. 67A-67E and FIG. 68 describe shoe sole structuralinventions that are formed with an upper surface to conform, or at leastbe complementary, to the all or most or at least part of the shape ofthe wearer's foot sole, whether under a body weight load or unloaded,but without rounded stability sides as defined by the applicant. Assuch, FIGS. 66-68 are similar to FIGS. 38-40 above, but without therounded stability sides at the essential structural support andpropulsion elements, which are the base and lateral tuberosity of thecalcaneus, the heads of the first and fifth metatarsals, the base of thefifth metatarsal, and the first distal phalange, and with shoe solerounded side thickness variations, as measured in frontal plane crosssections as defined in this and earlier applications.

FIGS. 66A-66F, FIG. 67A-67E, and FIG. 68, like the many other variationsof the applicant's naturally rounded design described in thisapplication, show a shoe sole invention wherein both the upper, footsole-contacting surface of the shoe sole and the bottom,ground-contacting surface of the shoe sole mirror the contours of thebottom surface of the wearer's foot sole, forming in effect a flexiblethree dimensional mirror of the load-bearing portions of that foot solewhen bare.

The shoe sole shown in FIGS. 66-68 preferably include an insole layer, amidsole layer, and bottom sole layer, and variation in the thickness ofthe shoe sole, as measured in sagittal plane cross sections, like theheel lift common to most shoes, as well as a shoe upper.

FIG. 69A-69D shows the implications of relative difference in range ofmotions between forefoot, midtarsal, and heel areas. FIG. 69A-D is amodification of FIG. 33 above, with the left side of the figures showingthe required range of motion for each area.

FIG. 69A shows a cross section of the forefoot area and therefore on theleft side shows the highest rounded sides (compared to the thickness ofthe shoe sole in the forefoot area) to accommodate the greater forefootrange of motion. The rounded side is sufficiently high to support theentire range of motion of the wearer's foot sole. Note that the sockliner or insole 2 is shown.

FIG. 69B shows a cross section of the midtarsal area at about the baseof the fifth metatarsal, which has somewhat less range of motion andtherefore the rounded sides are not as high (compared to the thicknessof the shoe sole at the midtarsal). FIG. 69C shows a cross section ofthe heel area, where the range of motion is the least, so the height ofthe rounded sides is relatively least of the three general areas (whencompared to the thickness of the shoe sole in the heel area).

Each of the three general areas, forefoot, midtarsal and heel, haverounded sides that differ relative to the high of those sides comparedto the thickness of the shoe sole in the same area. At the same time,note that the absolute height of the rounded sides is about the same forall three areas and the contours have a similar outward appearance, eventhough the actual structure differences are quite significant as shownin cross section.

In addition, the rounded sides shown in FIG. 69A-D can be abbreviated tosupport only those essential structural support and propulsion elementsidentified in FIG. 40 above. The essential structural support elementsare the base and lateral tuberosity of the calcaneus 95, the heads ofthe metatarsals 96, and the base of the fifth metatarsal 97. Theessential propulsion element is the head of the first distal phalange98.

FIG. 70 shows a similar view of a bottom sole structure 149, but with noside sections. The areas under the forefoot 126, heel 125, and base ofthe fifth metatarsal 97 would not be glued or attached firmly, while theother area (or most of it) would be glued or firmly attached. FIG. 70also shows a modification of the outer periphery of the convention shoesole 36: the typical indentation at the base of the fifth metatarsal isremoved, replaced by a fairly straight line 100.

FIG. 71 shows a similar structure to FIG. 70, but with only the sectionunder the forefoot 126 unglued or not firmly attached; the rest of thebottom sole 149 (or most of it) would be glued or firmly attached.

FIGS. 72G-72H show shoe soles with only one or more, but not all, of theessential stability elements (the use of all of which is stillpreferred) but which, based on FIG. 63, still represent major stabilityimprovements over existing footwear. This approach of abbreviatingstructural support to a few elements has the economic advantage of beingcapable of construction using conventional flat sheets of shoe solematerial, since the individual elements can be bent up to the rounded ofthe wearer's foot with reasonable accuracy and without difficulty.Whereas a continuous naturally rounded side that extends all of, or evena significant portion of, the way around the wearer's foot sole wouldbuckle partially since a flat surface cannot be accurately fitted to arounded surface; hence, injection molding is required for accuracy.

The features of FIGS. 72G-72H can be used in combination with thedesigns shown in this application. Further, various combinations ofabbreviated structural support elements may be utilized other than thosespecifically illustrated in the figures.

FIG. 72G shows a shoe sole combining the additional stabilitycorrections 96 a, 96 b, and 98 a supporting the first and fifthmetatarsal heads and distal phalange heads. The dashed line 98 a′represents a symmetrical optional stability addition on the lateral sidefor the heads of the second through fifth distal phalanges, which areless important for stability.

FIG. 72H shows a shoe sole with symmetrical stability additions 96 a and96 b. Besides being a major improvement in stability over existingfootwear, this design is aesthetically pleasing and could even be usedwith high heel type shoes, especially those for women, but also anyother form of footwear where there is a desire to retain relativelyconventional looks or where the shear height of the heel or heel liftprecludes stability side corrections at the heel or the base of thefifth metatarsal because of the required extreme thickness of the sides.This approach can also be used where it is desirable to leave the heelarea conventional, since providing both firmness and flexibility in theheel is more difficult that in other areas of the shoe sole since theshoe sole thickness is usually much greater there; consequently, it iseasier, less expensive in terms of change, and less of a risk indeparting from well understood prior art just to provide additionalstability corrections to the forefoot and/or base of the fifthmetatarsal area only.

Since the shoe sole thickness of the forefoot can be kept relativelythin, even with very high heels, the additional stability correctionscan be kept relatively inconspicuous. They can even be extended beyondthe load-bearing range of motion of the wearer's foot sole, even to wrapall the way around the upper portion of the foot in a strictlyornamental way (although they can also play a part in the shoe upper'sstructure), as a modification of the strap, for example, often seen onconventional loafers.

FIGS. 73A-73D show close-up cross sections of shoe soles modified withthe applicant's inventions for deformation sipes.

FIG. 73A shows a cross section of a design with deformation sipes in theform of channels, but with most of the channels filled with a material170 flexible enough that it still allows the shoe sole to deform likethe human foot. FIG. 73B shows a similar cross section with the channelsipes extending completely through the shoe sole, but with theintervening spaces also filled with a flexible material 170 like FIG.73A; a flexible connecting top layer 123 can also be used, but is notshown. The relative size and shape of the sipes can vary almostinfinitely. The relative proportion of flexible material 170 can vary,filling all or nearly all of the sipes, or only a small portion, and canvary between sipes in a consistent or even random pattern. As before,the exact structure of the sipes and filler material 170 can vary widelyand still provide the same benefit, though some variations will be moreeffective than others. Besides the flexible connecting utility of thefiller material 170, it also serves to keep out pebbles and other debristhat can be caught in the sipes, allowing relatively normal bottom soletread patterns to be created.

FIG. 73C shows a similar cross section of a design with deformationsipes in the form of channels that penetrate the shoe sole completelyand are connected by a flexible material 170 which does not reach theupper surface 30 of the shoe sole 28. Such an approach creates cancreate and upper shoe sole surface similar to that of the trademarkedMaseur® sandals, but one where the relative positions of the varioussections of the upper surface of the shoe sole will vary between eachother as the shoe sole bends up or down to conform to the naturaldeformation of the foot. The shape of the channels should be such thatthe resultant shape of the shoe sole sections would be similar butrounder than those honeycombed shapes of FIG. 14D of the '509application; in fact, like the Maseur sandals, cylindrical with arounded or beveled upper surface is probably optimal. The relativeposition of the flexible connecting material 170 can vary widely andstill provide the essential benefit. Preferably, the attachment of theshoe uppers would be to the upper surface of the flexible connectingmaterial 170.

A benefit of the FIG. 73C design is that the resulting upper surface 30of the shoe sole can change relative to the surface of the foot sole dueto natural deformation during normal foot motion. The relative motionmakes practical the direct contact between shoe sole and foot solewithout intervening insoles or socks, even in an athletic shoe. Thisconstant motion between the two surfaces allows the upper surface of theshoe sole to be roughened to stimulate the development of tough calluses(called a “Seri boot”), as described at the end of FIG. 10 above,without creating points of irritation from constant, unrelieved rubbingof exactly the same corresponding shoe sole and foot sole points ofcontact.

FIG. 73C shows a similar cross section of a design with deformationsipes in the form of angled channels in roughly and inverted V shape.Such a structure allows deformation bending freely both up and down; incontrast deformation slits can only be bent up and channels withparallel side walls 151 generally offer only a limited range of downwardmotion. The FIG. 73D angled channels would be particularly useful in theforefoot area to allow the shoe sole to conform to the natural roundedof the toes, which curl up and then down. As before, the exact structureof the angle channels can vary widely and still provide the samebenefit, though some variations will be more effective than others.Finally, though not shown, deformation slits can be aligned abovedeformation channels, in a sense continuing the channel in circumscribedform.

FIG. 74 shows sagittal plane shoe sole thickness variations, such asheel lifts 38 and forefoot lifts 40, and how the rounded sides 28 aequal and therefore vary with those varying thicknesses, as discussed inconnection with FIG. 31.

FIG. 75 shows, in FIGS. 75A-75C a method, known from the prior art, forassembling the midsole shoe sole structure of the present invention,showing in FIG. 75C the general concept of inserting the insertablemidsole orthotic 145 into the shoe upper and sole combination in thesame very simple manner as an intended wearer inserts his foot into theshoe upper and sole combination. FIGS. 75A and 75B show a similarinsertion method for the bottom sole 149.

The combinations of the many elements the applicant's inventionintroduced in the preceding figures are shown because those embodimentsare considered to be at least among the most useful. However, many otheruseful combinations embodiments are also clearly possible, but cannot beshown simply because of the impossibility of showing them all whilemaintaining a reasonable brevity and conciseness in what is already anunavoidably long description due to the inherently highly interconnectednature of the inventions shown herein, each of which can operateindependently or as part of a combination of others.

Therefore, any combination that is not explicitly described above isimplicit in the overall invention of this application and, consequently,any part of any of the preceding FIGS. 1-75 and/or textual specificationcan be combined with any other part of any one or more other of theFIGS. 1-75 and/or textual specification of this application to make newand useful improvements over the existing art.

In addition, any unique new part of any of the preceding FIGS. 1-73and/or associated textual specification can be considered by itselfalone as an individual improvement over the existing art.

The foregoing shoe designs meet the objectives of this invention asstated above. However, it will clearly be understood by those skilled inthe art that the foregoing description has been made in terms of thepreferred embodiments and various changes and modifications may be madewithout departing from the scope of the present invention which is to bedefined by the appended claims.

1. A shoe comprising: a shoe upper and a shoe sole including a least abottom sole; at least a portion of said shoe sole being formed by aninsertable midsole orthotic; at least a portion of the sides of saidshoe upper being attached directly to the bottom sole such that the shoeupper envelopes, on the outside, at least the insertable midsoleorthotic of said shoe sole; and at least a part of an inner and an outersurface of the shoe sole being concavely rounded relative to an intendedwearer's foot location inside the shoe, as viewed in a frontal planecross section when the shoe sole is in an upright, unloaded condition.2. A shoe as claimed in claim 1 wherein said insertable midsole orthoticis removable from the shoe and insertable into said shoe upper throughan opening in the shoe upper provided for entry and exit of an intendedwearer's foot into and out of said shoe.
 3. A shoe sole for a shoe orother footwear, such as an athletic shoe or street shoe, comprising: atleast a bottom sole, a midsole, an inner surface and an outer surface;at least a part of said outer surface having a convexly rounded shape,as seen in a frontal plane cross-section from outside the shoe sole whenthe shoe sole is in an upright, unloaded condition; and wherein saidmidsole includes an insertable midsole orthotic which is removable fromsaid shoe sole and which forms at least a portion of said convexlyrounded part of said outer surface.
 4. A shoe sole as claimed in claim 3wherein said insertable midsole orthotic of said midsole is releasablysecured to at least one of said shoe sole or a shoe of which said shoesole forms a part, by a releasable securing structure selected from thegroup consisting of mechanical fasteners, a snap fit, adhesives,interlocking surfaces, and combinations thereof.
 5. A shoe sole asclaimed in claim 1 wherein the shoe sole further comprises at least onecompartment containing a fluid, a flow regulator, a pressure sensor tomonitor the compartment pressure, and a control system in communicationwith said compartment and said flow regulator, said control system iscapable of automatically adjusting the pressure in said compartmentbased on sensing of a predetermined pressure is said compartmentresulting from impact of the shoe sole with the ground surface.
 6. Ashoe sole as claimed in claim 5 wherein said control system is acomputer processor in electrical communication with said flow regulatorand said sensor and wherein said computer processor receives and storespressure data from said sensor and computes said predetermined pressure.7. A shoe sole as claimed in claim 6, wherein said orthotic section iscapable of being permanently affixed in said shoe sole.
 8. A shoe soleas claimed in claim 5 wherein said shoe sole comprises at least twocompartments and a duct communicating between said at least twocompartments.
 9. A shoe sole as claimed in claim 6 wherein said shoesole comprises at least two compartments and a duct communicatingbetween said at least two compartments.
 10. A shoe sole as claimed inclaim 7 wherein said shoe sole comprises at least two compartments and aduct communicating between said at least two compartments.
 11. Anorthotic inner shoe which comprises: an insertable midsole orthoticsized to fit inside and form part of the sole of a shoe designed toreceive and retain said insertable midsole orthotic; a secondary outersole on at least a portion of the outer surface of the insertablemidsole orthotic to provide traction or wear resistance when saidorthotic inner shoe is worn without the shoe designed to receive andretain said insertable midsole orthotic; and a device associated withthe insertable midsole orthotic for retaining the orthotic inner shoe onan intended wearer's foot when worn without the shoe designed to receiveand retain the insertable midsole orthotic.
 12. The orthotic inner shoeas claimed in claim 11 wherein the device for retaining the orthoticinner shoe on an intended wearer's foot comprises an integral secondaryupper.
 13. The orthotic inner shoe as claimed in claim 11 wherein theupper portion of the insertable midsole orthotic provides the correctiveorthotic effect and the upper portion of the insertable midsole orthoticcomprises less than half of the thickness of the sole of the insertablemidsole orthotic.
 14. The orthotic inner shoe as claimed in claim 11,further comprising at least one computer controlled compartment, andwherein the computer control for the computer controlled compartment islocated in the upper portion of the insertable midsole orthotic and theupper portion of the insertable midsole orthotic comprises less thanhalf of the thickness of the sole of the insertable midsole orthotic.